09-resolving-the-bill/interleaving.ipynb

   1 {
   2  "cells": [
   3   {
   4    "cell_type": "markdown",
   5    "metadata": {},
   6    "source": [
   7     "# Interleaved strings\n",
   8     "\n",
   9     "Given two strings a and b and a target c, could c be formed form some interleaving/merge of a and b?\n",
  10     "\n",
  11     "For example,\n",
  12     "Given:\n",
  13     "s1 = \"aabcc\",\n",
  14     "s2 = \"dbbca\",\n",
  15     "\n",
  16     "When s3 = \"aadbbcbcac\", return true.\n",
  17     "When s3 = \"aadbbbaccc\", return false."
  18    ]
  19   },
  20   {
  21    "cell_type": "code",
  22    "execution_count": 1,
  23    "metadata": {
  24     "collapsed": true
  25    },
  26    "outputs": [],
  27    "source": [
  28     "import random\n",
  29     "import string"
  30    ]
  31   },
  32   {
  33    "cell_type": "code",
  34    "execution_count": 2,
  35    "metadata": {
  36     "collapsed": true
  37    },
  38    "outputs": [],
  39    "source": [
  40     "s1 = \"aabcc\"\n",
  41     "s2 = \"dbbca\"\n",
  42     "\n",
  43     "s3t = \"aadbbcbcac\"\n",
  44     "s3f = \"aadbbbaccc\""
  45    ]
  46   },
  47   {
  48    "cell_type": "code",
  49    "execution_count": 3,
  50    "metadata": {},
  51    "outputs": [
  52     {
  53      "data": {
  54       "text/plain": [
  55        "[(0, ''), (1, 'a'), (2, 'aa'), (3, 'aab'), (4, 'aabc'), (5, 'aabcc')]"
  56       ]
  57      },
  58      "execution_count": 3,
  59      "metadata": {},
  60      "output_type": "execute_result"
  61     }
  62    ],
  63    "source": [
  64     "[(i, s1[:i]) for i in range(len(s1)+1)]"
  65    ]
  66   },
  67   {
  68    "cell_type": "markdown",
  69    "metadata": {},
  70    "source": [
  71     "`dp_table[i, j]` is True if first `i` + `j` characters of `s3` can be formed from interleaving of first `i` characters of `s1` and first `j` characters of `s2`."
  72    ]
  73   },
  74   {
  75    "cell_type": "code",
  76    "execution_count": 5,
  77    "metadata": {},
  78    "outputs": [
  79     {
  80      "data": {
  81       "text/plain": [
  82        "[[True, False, False, False, False, False],\n",
  83        " [False, False, False, False, False, False],\n",
  84        " [False, False, False, False, False, False],\n",
  85        " [False, False, False, False, False, False],\n",
  86        " [False, False, False, False, False, False],\n",
  87        " [False, False, False, False, False, False]]"
  88       ]
  89      },
  90      "execution_count": 5,
  91      "metadata": {},
  92      "output_type": "execute_result"
  93     }
  94    ],
  95    "source": [
  96     "dp_table = [[False] * (len(s1) + 1) for _ in range(len(s2) + 1)]\n",
  97     "dp_table[0][0] = True\n",
  98     "dp_table"
  99    ]
 100   },
 101   {
 102    "cell_type": "code",
 103    "execution_count": 4,
 104    "metadata": {
 105     "scrolled": true
 106    },
 107    "outputs": [
 108     {
 109      "data": {
 110       "text/plain": [
 111        "{(0, 0): False,\n",
 112        " (0, 1): False,\n",
 113        " (0, 2): False,\n",
 114        " (0, 3): False,\n",
 115        " (0, 4): False,\n",
 116        " (0, 5): False,\n",
 117        " (1, 0): False,\n",
 118        " (1, 1): False,\n",
 119        " (1, 2): False,\n",
 120        " (1, 3): False,\n",
 121        " (1, 4): False,\n",
 122        " (1, 5): False,\n",
 123        " (2, 0): False,\n",
 124        " (2, 1): False,\n",
 125        " (2, 2): False,\n",
 126        " (2, 3): False,\n",
 127        " (2, 4): False,\n",
 128        " (2, 5): False,\n",
 129        " (3, 0): False,\n",
 130        " (3, 1): False,\n",
 131        " (3, 2): False,\n",
 132        " (3, 3): False,\n",
 133        " (3, 4): False,\n",
 134        " (3, 5): False,\n",
 135        " (4, 0): False,\n",
 136        " (4, 1): False,\n",
 137        " (4, 2): False,\n",
 138        " (4, 3): False,\n",
 139        " (4, 4): False,\n",
 140        " (4, 5): False,\n",
 141        " (5, 0): False,\n",
 142        " (5, 1): False,\n",
 143        " (5, 2): False,\n",
 144        " (5, 3): False,\n",
 145        " (5, 4): False,\n",
 146        " (5, 5): False}"
 147       ]
 148      },
 149      "execution_count": 4,
 150      "metadata": {},
 151      "output_type": "execute_result"
 152     }
 153    ],
 154    "source": [
 155     "dp_table = {(i, j): False\n",
 156     "           for i in range(len(s1)+1)\n",
 157     "           for j in range(len(s2)+1)}\n",
 158     "dp_table"
 159    ]
 160   },
 161   {
 162    "cell_type": "code",
 163    "execution_count": 5,
 164    "metadata": {
 165     "collapsed": true
 166    },
 167    "outputs": [],
 168    "source": [
 169     "def show_table(table):\n",
 170     "    return '\\n'.join(\n",
 171     "        ' '.join(str(table[i, j])[0] for j in sorted(set([k[1] for k in table])))\n",
 172     "        for i in sorted(set([k[0] for k in table])))        "
 173    ]
 174   },
 175   {
 176    "cell_type": "code",
 177    "execution_count": 6,
 178    "metadata": {
 179     "collapsed": true
 180    },
 181    "outputs": [],
 182    "source": [
 183     "def show_table(table):\n",
 184     "    return '\\n'.join(\n",
 185     "        ' '.join('T' if table[i, j] else '.' for j in sorted(set([k[1] for k in table])))\n",
 186     "        for i in sorted(set([k[0] for k in table])))        "
 187    ]
 188   },
 189   {
 190    "cell_type": "code",
 191    "execution_count": 7,
 192    "metadata": {},
 193    "outputs": [
 194     {
 195      "name": "stdout",
 196      "output_type": "stream",
 197      "text": [
 198       ". . . . . .\n",
 199       ". . . . . .\n",
 200       ". . . . . .\n",
 201       ". . . . . .\n",
 202       ". . . . . .\n",
 203       ". . . . . .\n"
 204      ]
 205     }
 206    ],
 207    "source": [
 208     "print(show_table(dp_table))"
 209    ]
 210   },
 211   {
 212    "cell_type": "code",
 213    "execution_count": 8,
 214    "metadata": {},
 215    "outputs": [
 216     {
 217      "name": "stdout",
 218      "output_type": "stream",
 219      "text": [
 220       "aabcc dbbca aadbbcbcac\n",
 221       "aa 0 0 ! ! ! True\n",
 222       "s2 0 1 ! d a False\n",
 223       "s2 0 2 ! b a False\n",
 224       "s2 0 3 ! b d False\n",
 225       "s2 0 4 ! c b False\n",
 226       "s2 0 5 ! a b False\n",
 227       "s1 1 0 a ! a True\n",
 228       "xx 1 1 a d a False\n",
 229       "xx 1 2 a b d False\n",
 230       "xx 1 3 a b b False\n",
 231       "xx 1 4 a c b False\n",
 232       "xx 1 5 a a c False\n",
 233       "s1 2 0 a ! a True\n",
 234       "s2 2 1 a d d True\n",
 235       "s2 2 2 a b b True\n",
 236       "s2 2 3 a b b True\n",
 237       "s2 2 4 a c c True\n",
 238       "xx 2 5 a a b False\n",
 239       "s1 3 0 b ! d False\n",
 240       "s1 3 1 b d b True\n",
 241       "s2 3 2 b b b True\n",
 242       "s1 3 2 b b b True\n",
 243       "xx 3 3 b b c False\n",
 244       "s1 3 4 b c b True\n",
 245       "xx 3 5 b a c False\n",
 246       "s1 4 0 c ! b False\n",
 247       "xx 4 1 c d b False\n",
 248       "s1 4 2 c b c True\n",
 249       "s2 4 3 c b b True\n",
 250       "s2 4 4 c c c True\n",
 251       "s1 4 4 c c c True\n",
 252       "s2 4 5 c a a True\n",
 253       "s1 5 0 c ! b False\n",
 254       "xx 5 1 c d c False\n",
 255       "xx 5 2 c b b False\n",
 256       "s1 5 3 c b c True\n",
 257       "xx 5 4 c c a False\n",
 258       "s1 5 5 c a c True\n",
 259       "T . . . . .\n",
 260       "T . . . . .\n",
 261       "T T T T T .\n",
 262       ". T T . T .\n",
 263       ". . T T T T\n",
 264       ". . . T . T\n"
 265      ]
 266     },
 267     {
 268      "data": {
 269       "text/plain": [
 270        "{(1, 0): (0, 0, 'a', 's1'),\n",
 271        " (2, 0): (1, 0, 'a', 's1'),\n",
 272        " (2, 1): (2, 0, 'd', 's2'),\n",
 273        " (2, 2): (2, 1, 'b', 's2'),\n",
 274        " (2, 3): (2, 2, 'b', 's2'),\n",
 275        " (2, 4): (2, 3, 'c', 's2'),\n",
 276        " (3, 1): (2, 1, 'b', 's1'),\n",
 277        " (3, 2): (2, 2, 'b', 's1'),\n",
 278        " (3, 4): (2, 4, 'b', 's1'),\n",
 279        " (4, 2): (3, 2, 'c', 's1'),\n",
 280        " (4, 3): (4, 2, 'b', 's2'),\n",
 281        " (4, 4): (3, 4, 'c', 's1'),\n",
 282        " (4, 5): (4, 4, 'a', 's2'),\n",
 283        " (5, 3): (4, 3, 'c', 's1'),\n",
 284        " (5, 5): (4, 5, 'c', 's1')}"
 285       ]
 286      },
 287      "execution_count": 8,
 288      "metadata": {},
 289      "output_type": "execute_result"
 290     }
 291    ],
 292    "source": [
 293     "s3 = s3t\n",
 294     "\n",
 295     "print(s1, s2, s3)\n",
 296     "\n",
 297     "dp_table = {(i, j): False\n",
 298     "           for i in range(len(s1)+1)\n",
 299     "           for j in range(len(s2)+1)}\n",
 300     "\n",
 301     "backpointers = {}\n",
 302     "\n",
 303     "for i in range(len(s1)+1):\n",
 304     "    for j in range(len(s2)+1):\n",
 305     "        if i == 0 and j == 0:\n",
 306     "            dp_table[i, j] = True\n",
 307     "            print('aa', i, j, '!', '!', '!', dp_table[i, j])\n",
 308     "        elif i == 0:\n",
 309     "            # extend by character from s2\n",
 310     "            if dp_table[i, j-1] and s2[j-1] == s3[i+j-1]:\n",
 311     "                dp_table[i, j] = True\n",
 312     "                backpointers[i, j] = (i, j-1, s2[j-1], 's2')\n",
 313     "            print('s2', i, j, '!', s2[j-1], s3[i+j-1], dp_table[i, j])\n",
 314     "        elif j == 0:\n",
 315     "            # extend by character from s1\n",
 316     "            if dp_table[i-1, j] and s1[i-1] == s3[i+j-1]:\n",
 317     "                dp_table[i, j] = True\n",
 318     "                backpointers[i, j] = (i-1, j, s1[i-1], 's1')\n",
 319     "            print('s1', i, j, s1[i-1], '!', s3[i+j-1], dp_table[i, j])\n",
 320     "        else:\n",
 321     "            # extend by character from s2\n",
 322     "            if dp_table[i, j-1] and s2[j-1] == s3[i+j-1]:\n",
 323     "                dp_table[i, j] = True\n",
 324     "                backpointers[i, j] = (i, j-1, s2[j-1], 's2')\n",
 325     "                print('s2', i, j, s1[i-1], s2[j-1], s3[i+j-1], dp_table[i, j])                \n",
 326     "            # extend by character from s1\n",
 327     "            if dp_table[i-1, j] and s1[i-1] == s3[i+j-1]:\n",
 328     "                dp_table[i, j] = True\n",
 329     "                backpointers[i, j] = (i-1, j, s1[i-1], 's1')                \n",
 330     "                print('s1', i, j, s1[i-1], s2[j-1], s3[i+j-1], dp_table[i, j])\n",
 331     "            if not dp_table[i, j]:\n",
 332     "                print('xx', i, j, s1[i-1], s2[j-1], s3[i+j-1], dp_table[i, j])\n",
 333     "\n",
 334     "print(show_table(dp_table))\n",
 335     "backpointers"
 336    ]
 337   },
 338   {
 339    "cell_type": "code",
 340    "execution_count": 11,
 341    "metadata": {
 342     "collapsed": true
 343    },
 344    "outputs": [],
 345    "source": [
 346     "def is_interleave(seq1, seq2, seq3, return_backpointers=False, return_table=False, debug=False):\n",
 347     "    \"\"\"Return true if seq3 is some interleaved merge of seq1 and seq2.\n",
 348     "    If return_backpointers, also return the set of backpointers to\n",
 349     "    reconstruct the interleaving\"\"\"\n",
 350     "    \n",
 351     "    # dp_table[i, j] is True if first i+j characters of seq is made up of \n",
 352     "    # an interleaving of the first i characters of seq1 and the \n",
 353     "    # first j characters of seq2\n",
 354     "    \n",
 355     "    if len(seq1) + len(seq2) != len(seq3):\n",
 356     "        if return_backpointers or return_table:\n",
 357     "            retval = [False]\n",
 358     "            if return_backpointers:\n",
 359     "                retval += [{}]\n",
 360     "            if return_table:\n",
 361     "                retval += [{}]\n",
 362     "            return tuple(retval)\n",
 363     "        else:\n",
 364     "            return False\n",
 365     "    \n",
 366     "    dp_table = {(i, j): False\n",
 367     "               for i in range(len(seq1)+1)\n",
 368     "               for j in range(len(seq2)+1)}\n",
 369     "\n",
 370     "    backpointers = {}\n",
 371     "\n",
 372     "    for i in range(len(seq1)+1):\n",
 373     "        for j in range(len(seq2)+1):\n",
 374     "            if i == 0 and j == 0:\n",
 375     "                dp_table[i, j] = True\n",
 376     "                if debug: print('xxxx', i, j, '!', '!', '!', dp_table[i, j])\n",
 377     "            elif i == 0:\n",
 378     "                # extend by character from seq2\n",
 379     "                if dp_table[i, j-1] and seq2[j-1] == seq3[i+j-1]:\n",
 380     "                    dp_table[i, j] = True\n",
 381     "                    backpointers[i, j] = (i, j-1, seq2[j-1], 'seq2')\n",
 382     "                if debug: print('seq2', i, j, '!', seq2[j-1], seq3[i+j-1], dp_table[i, j])\n",
 383     "            elif j == 0:\n",
 384     "                # extend by character from seq1\n",
 385     "                if dp_table[i-1, j] and seq1[i-1] == seq3[i+j-1]:\n",
 386     "                    dp_table[i, j] = True\n",
 387     "                    backpointers[i, j] = (i-1, j, seq1[i-1], 'seq1')\n",
 388     "                if debug: print('seq1', i, j, seq1[i-1], '!', seq3[i+j-1], dp_table[i, j])\n",
 389     "            else:\n",
 390     "                # extend by character from seq2\n",
 391     "                if dp_table[i, j-1] and seq2[j-1] == seq3[i+j-1]:\n",
 392     "                    dp_table[i, j] = True\n",
 393     "                    backpointers[i, j] = (i, j-1, seq2[j-1], 'seq2')\n",
 394     "                    if debug: print('seq2', i, j, seq1[i-1], seq2[j-1], seq3[i+j-1], dp_table[i, j])                \n",
 395     "                # extend by character from seq1\n",
 396     "                if dp_table[i-1, j] and seq1[i-1] == seq3[i+j-1]:\n",
 397     "                    dp_table[i, j] = True\n",
 398     "                    backpointers[i, j] = (i-1, j, seq1[i-1], 'seq1')                \n",
 399     "                    if debug: print('seq1', i, j, seq1[i-1], seq2[j-1], seq3[i+j-1], dp_table[i, j])\n",
 400     "                if not dp_table[i, j]:\n",
 401     "                    if debug: print('xxxx', i, j, seq1[i-1], seq2[j-1], seq3[i+j-1], dp_table[i, j])\n",
 402     "\n",
 403     "    if return_backpointers or return_table:\n",
 404     "        retval = [dp_table[len(seq1), len(seq2)]]\n",
 405     "        if return_backpointers:\n",
 406     "            retval += [backpointers]\n",
 407     "        if return_table:\n",
 408     "            retval += [dp_table]\n",
 409     "        return tuple(retval)\n",
 410     "    else:\n",
 411     "        return dp_table[len(seq1), len(seq2)]"
 412    ]
 413   },
 414   {
 415    "cell_type": "code",
 416    "execution_count": 12,
 417    "metadata": {},
 418    "outputs": [
 419     {
 420      "data": {
 421       "text/plain": [
 422        "True"
 423       ]
 424      },
 425      "execution_count": 12,
 426      "metadata": {},
 427      "output_type": "execute_result"
 428     }
 429    ],
 430    "source": [
 431     "is_interleave(s1, s2, s3t)"
 432    ]
 433   },
 434   {
 435    "cell_type": "code",
 436    "execution_count": 13,
 437    "metadata": {},
 438    "outputs": [
 439     {
 440      "data": {
 441       "text/plain": [
 442        "(True,\n",
 443        " {(1, 0): (0, 0, 'a', 'seq1'),\n",
 444        "  (2, 0): (1, 0, 'a', 'seq1'),\n",
 445        "  (2, 1): (2, 0, 'd', 'seq2'),\n",
 446        "  (2, 2): (2, 1, 'b', 'seq2'),\n",
 447        "  (2, 3): (2, 2, 'b', 'seq2'),\n",
 448        "  (2, 4): (2, 3, 'c', 'seq2'),\n",
 449        "  (3, 1): (2, 1, 'b', 'seq1'),\n",
 450        "  (3, 2): (2, 2, 'b', 'seq1'),\n",
 451        "  (3, 4): (2, 4, 'b', 'seq1'),\n",
 452        "  (4, 2): (3, 2, 'c', 'seq1'),\n",
 453        "  (4, 3): (4, 2, 'b', 'seq2'),\n",
 454        "  (4, 4): (3, 4, 'c', 'seq1'),\n",
 455        "  (4, 5): (4, 4, 'a', 'seq2'),\n",
 456        "  (5, 3): (4, 3, 'c', 'seq1'),\n",
 457        "  (5, 5): (4, 5, 'c', 'seq1')})"
 458       ]
 459      },
 460      "execution_count": 13,
 461      "metadata": {},
 462      "output_type": "execute_result"
 463     }
 464    ],
 465    "source": [
 466     "is_interleave(s1, s2, s3t, return_backpointers=True)"
 467    ]
 468   },
 469   {
 470    "cell_type": "code",
 471    "execution_count": 14,
 472    "metadata": {
 473     "scrolled": true
 474    },
 475    "outputs": [
 476     {
 477      "data": {
 478       "text/plain": [
 479        "(True,\n",
 480        " {(1, 0): (0, 0, 'a', 'seq1'),\n",
 481        "  (2, 0): (1, 0, 'a', 'seq1'),\n",
 482        "  (2, 1): (2, 0, 'd', 'seq2'),\n",
 483        "  (2, 2): (2, 1, 'b', 'seq2'),\n",
 484        "  (2, 3): (2, 2, 'b', 'seq2'),\n",
 485        "  (2, 4): (2, 3, 'c', 'seq2'),\n",
 486        "  (3, 1): (2, 1, 'b', 'seq1'),\n",
 487        "  (3, 2): (2, 2, 'b', 'seq1'),\n",
 488        "  (3, 4): (2, 4, 'b', 'seq1'),\n",
 489        "  (4, 2): (3, 2, 'c', 'seq1'),\n",
 490        "  (4, 3): (4, 2, 'b', 'seq2'),\n",
 491        "  (4, 4): (3, 4, 'c', 'seq1'),\n",
 492        "  (4, 5): (4, 4, 'a', 'seq2'),\n",
 493        "  (5, 3): (4, 3, 'c', 'seq1'),\n",
 494        "  (5, 5): (4, 5, 'c', 'seq1')},\n",
 495        " {(0, 0): True,\n",
 496        "  (0, 1): False,\n",
 497        "  (0, 2): False,\n",
 498        "  (0, 3): False,\n",
 499        "  (0, 4): False,\n",
 500        "  (0, 5): False,\n",
 501        "  (1, 0): True,\n",
 502        "  (1, 1): False,\n",
 503        "  (1, 2): False,\n",
 504        "  (1, 3): False,\n",
 505        "  (1, 4): False,\n",
 506        "  (1, 5): False,\n",
 507        "  (2, 0): True,\n",
 508        "  (2, 1): True,\n",
 509        "  (2, 2): True,\n",
 510        "  (2, 3): True,\n",
 511        "  (2, 4): True,\n",
 512        "  (2, 5): False,\n",
 513        "  (3, 0): False,\n",
 514        "  (3, 1): True,\n",
 515        "  (3, 2): True,\n",
 516        "  (3, 3): False,\n",
 517        "  (3, 4): True,\n",
 518        "  (3, 5): False,\n",
 519        "  (4, 0): False,\n",
 520        "  (4, 1): False,\n",
 521        "  (4, 2): True,\n",
 522        "  (4, 3): True,\n",
 523        "  (4, 4): True,\n",
 524        "  (4, 5): True,\n",
 525        "  (5, 0): False,\n",
 526        "  (5, 1): False,\n",
 527        "  (5, 2): False,\n",
 528        "  (5, 3): True,\n",
 529        "  (5, 4): False,\n",
 530        "  (5, 5): True})"
 531       ]
 532      },
 533      "execution_count": 14,
 534      "metadata": {},
 535      "output_type": "execute_result"
 536     }
 537    ],
 538    "source": [
 539     "is_interleave(s1, s2, s3t, return_backpointers=True, return_table=True)"
 540    ]
 541   },
 542   {
 543    "cell_type": "code",
 544    "execution_count": 15,
 545    "metadata": {},
 546    "outputs": [
 547     {
 548      "data": {
 549       "text/plain": [
 550        "False"
 551       ]
 552      },
 553      "execution_count": 15,
 554      "metadata": {},
 555      "output_type": "execute_result"
 556     }
 557    ],
 558    "source": [
 559     "is_interleave(s1, s2, s3f)"
 560    ]
 561   },
 562   {
 563    "cell_type": "code",
 564    "execution_count": 16,
 565    "metadata": {},
 566    "outputs": [
 567     {
 568      "name": "stdout",
 569      "output_type": "stream",
 570      "text": [
 571       "xxxx 0 0 ! ! ! True\n",
 572       "seq2 0 1 ! b a False\n",
 573       "seq2 0 2 ! b a False\n",
 574       "seq2 0 3 ! b a False\n",
 575       "seq1 1 0 a ! a True\n",
 576       "xxxx 1 1 a b a False\n",
 577       "xxxx 1 2 a b a False\n",
 578       "xxxx 1 3 a b b False\n",
 579       "seq1 2 0 a ! a True\n",
 580       "xxxx 2 1 a b a False\n",
 581       "xxxx 2 2 a b b False\n",
 582       "xxxx 2 3 a b a False\n",
 583       "seq1 3 0 a ! a True\n",
 584       "seq2 3 1 a b b True\n",
 585       "xxxx 3 2 a b a False\n",
 586       "xxxx 3 3 a b b False\n",
 587       "seq1 4 0 a ! b False\n",
 588       "seq1 4 1 a b a True\n",
 589       "seq2 4 2 a b b True\n",
 590       "seq2 4 3 a b b True\n"
 591      ]
 592     },
 593     {
 594      "data": {
 595       "text/plain": [
 596        "(True,\n",
 597        " {(1, 0): (0, 0, 'a', 'seq1'),\n",
 598        "  (2, 0): (1, 0, 'a', 'seq1'),\n",
 599        "  (3, 0): (2, 0, 'a', 'seq1'),\n",
 600        "  (3, 1): (3, 0, 'b', 'seq2'),\n",
 601        "  (4, 1): (3, 1, 'a', 'seq1'),\n",
 602        "  (4, 2): (4, 1, 'b', 'seq2'),\n",
 603        "  (4, 3): (4, 2, 'b', 'seq2')})"
 604       ]
 605      },
 606      "execution_count": 16,
 607      "metadata": {},
 608      "output_type": "execute_result"
 609     }
 610    ],
 611    "source": [
 612     "is_interleave('aaaa', 'bbb', 'aaababb', return_backpointers=True, debug=True)"
 613    ]
 614   },
 615   {
 616    "cell_type": "code",
 617    "execution_count": 17,
 618    "metadata": {
 619     "collapsed": true
 620    },
 621    "outputs": [],
 622    "source": [
 623     "def show_backtrace(bps):\n",
 624     "    i = max([0] + [k[0] for k in bps])\n",
 625     "    j = max([0] + [k[1] for k in bps])\n",
 626     "    chars = ''\n",
 627     "    if (i, j) in bps:\n",
 628     "        while i != 0 or j != 0:\n",
 629     "            if bps[i, j][3] == 'seq1':\n",
 630     "                chars += bps[i, j][2].upper()\n",
 631     "            else:\n",
 632     "                chars += bps[i, j][2]\n",
 633     "            i, j = bps[i, j][0], bps[i, j][1] \n",
 634     "        return ''.join(list(reversed(chars)))\n",
 635     "    else:\n",
 636     "        return ''"
 637    ]
 638   },
 639   {
 640    "cell_type": "code",
 641    "execution_count": 18,
 642    "metadata": {
 643     "collapsed": true
 644    },
 645    "outputs": [],
 646    "source": [
 647     "def make_string(length, alphabet=None):\n",
 648     "    if not alphabet:\n",
 649     "        alphabet = 'abcdefgh'\n",
 650     "    return ''.join(random.choice(alphabet) for _ in range(length))    "
 651    ]
 652   },
 653   {
 654    "cell_type": "code",
 655    "execution_count": 19,
 656    "metadata": {},
 657    "outputs": [
 658     {
 659      "data": {
 660       "text/plain": [
 661        "'fddagfdacgbdggabhgcgfddecffbghccebhefghbchhhbfdfgc'"
 662       ]
 663      },
 664      "execution_count": 19,
 665      "metadata": {},
 666      "output_type": "execute_result"
 667     }
 668    ],
 669    "source": [
 670     "make_string(50)"
 671    ]
 672   },
 673   {
 674    "cell_type": "code",
 675    "execution_count": 20,
 676    "metadata": {
 677     "collapsed": true
 678    },
 679    "outputs": [],
 680    "source": [
 681     "def interleave(s1, s2, wander_limit=10, debug=False):\n",
 682     "    i1 = i2 = wander = 0\n",
 683     "    interleaved = []\n",
 684     "    while i1 <= len(s1) and i2 <= len(s2):\n",
 685     "        if i1 == len(s1):\n",
 686     "            if debug: print(i1, i2, wander, 'remaining s2', s2[i2:])\n",
 687     "            interleaved += s2[i2:]\n",
 688     "            i2 = len(s2) + 1\n",
 689     "        elif i2 == len(s2):\n",
 690     "            if debug: print(i1, i2, wander, 'remaining s1', s1[i1:])\n",
 691     "            interleaved += s1[i1:]\n",
 692     "            i1 = len(s1) + 1\n",
 693     "        else:\n",
 694     "            if wander == wander_limit:\n",
 695     "                step = -1\n",
 696     "            elif wander == -wander_limit:\n",
 697     "                step = +1\n",
 698     "            else:\n",
 699     "                step = random.choice([+1, -1])\n",
 700     "            if step == +1:\n",
 701     "                if debug: print(i1, i2, wander, 'adding', s1[i1])\n",
 702     "                interleaved += s1[i1]\n",
 703     "                i1 += 1\n",
 704     "                wander += 1\n",
 705     "            else:\n",
 706     "                if debug: print(i1, i2, wander, 'adding', s2[i2])\n",
 707     "                interleaved += s2[i2]\n",
 708     "                i2 += 1\n",
 709     "                wander -= 1\n",
 710     "    return ''.join(interleaved)\n",
 711     "            "
 712    ]
 713   },
 714   {
 715    "cell_type": "code",
 716    "execution_count": 21,
 717    "metadata": {},
 718    "outputs": [
 719     {
 720      "name": "stdout",
 721      "output_type": "stream",
 722      "text": [
 723       "0 0 0 adding x\n",
 724       "0 1 -1 adding y\n",
 725       "0 2 -2 adding x\n",
 726       "0 3 -3 adding g\n",
 727       "1 3 -2 adding h\n",
 728       "2 3 -1 adding d\n",
 729       "3 3 0 adding v\n",
 730       "3 4 -1 adding x\n",
 731       "3 5 -2 adding d\n",
 732       "4 5 -1 adding v\n",
 733       "4 6 -2 adding a\n",
 734       "5 6 -1 adding g\n",
 735       "6 6 0 adding w\n",
 736       "6 7 -1 adding v\n",
 737       "6 8 -2 adding e\n",
 738       "7 8 -1 adding u\n",
 739       "7 9 -2 adding w\n",
 740       "7 10 -3 adding x\n",
 741       "7 11 -4 adding e\n",
 742       "8 11 -3 adding d\n",
 743       "9 11 -2 adding w\n",
 744       "9 12 -3 adding c\n",
 745       "10 12 -2 adding z\n",
 746       "10 13 -3 adding y\n",
 747       "10 14 -4 adding h\n",
 748       "11 14 -3 adding g\n",
 749       "12 14 -2 adding z\n",
 750       "12 15 -3 adding x\n",
 751       "12 16 -4 adding w\n",
 752       "12 17 -5 adding e\n",
 753       "13 17 -4 adding w\n",
 754       "13 18 -5 adding f\n",
 755       "14 18 -4 adding z\n",
 756       "14 19 -5 adding f\n",
 757       "15 19 -4 adding b\n",
 758       "16 19 -3 adding u\n",
 759       "16 20 -4 remaining s1 gchd\n"
 760      ]
 761     },
 762     {
 763      "data": {
 764       "text/plain": [
 765        "('ghddageedchgeffbgchd',\n",
 766        " 'xyxvxvwvuwxwzyzxwwzu',\n",
 767        " 'xyxghdvxdvagwveuwxedwczyhgzxwewfzfbugchd',\n",
 768        " 40)"
 769       ]
 770      },
 771      "execution_count": 21,
 772      "metadata": {},
 773      "output_type": "execute_result"
 774     }
 775    ],
 776    "source": [
 777     "s1 = make_string(20)\n",
 778     "s2 = make_string(20, alphabet='uvwxyz')\n",
 779     "il = interleave(s1, s2, wander_limit=5, debug=True)\n",
 780     "s1, s2, il, len(il)"
 781    ]
 782   },
 783   {
 784    "cell_type": "code",
 785    "execution_count": 22,
 786    "metadata": {},
 787    "outputs": [
 788     {
 789      "name": "stdout",
 790      "output_type": "stream",
 791      "text": [
 792       "xxxx 0 0 ! ! ! True\n",
 793       "seq2 0 1 ! g x False\n",
 794       "seq2 0 2 ! h y False\n",
 795       "seq2 0 3 ! d x False\n",
 796       "seq2 0 4 ! d g False\n",
 797       "seq2 0 5 ! a h False\n",
 798       "seq2 0 6 ! g d False\n",
 799       "seq2 0 7 ! e v False\n",
 800       "seq2 0 8 ! e x False\n",
 801       "seq2 0 9 ! d d False\n",
 802       "seq2 0 10 ! c v False\n",
 803       "seq2 0 11 ! h a False\n",
 804       "seq2 0 12 ! g g False\n",
 805       "seq2 0 13 ! e w False\n",
 806       "seq2 0 14 ! f v False\n",
 807       "seq2 0 15 ! f e False\n",
 808       "seq2 0 16 ! b u False\n",
 809       "seq2 0 17 ! g w False\n",
 810       "seq2 0 18 ! c x False\n",
 811       "seq2 0 19 ! h e False\n",
 812       "seq2 0 20 ! d d False\n",
 813       "seq1 1 0 x ! x True\n",
 814       "xxxx 1 1 x g y False\n",
 815       "xxxx 1 2 x h x False\n",
 816       "xxxx 1 3 x d g False\n",
 817       "xxxx 1 4 x d h False\n",
 818       "xxxx 1 5 x a d False\n",
 819       "xxxx 1 6 x g v False\n",
 820       "xxxx 1 7 x e x False\n",
 821       "xxxx 1 8 x e d False\n",
 822       "xxxx 1 9 x d v False\n",
 823       "xxxx 1 10 x c a False\n",
 824       "xxxx 1 11 x h g False\n",
 825       "xxxx 1 12 x g w False\n",
 826       "xxxx 1 13 x e v False\n",
 827       "xxxx 1 14 x f e False\n",
 828       "xxxx 1 15 x f u False\n",
 829       "xxxx 1 16 x b w False\n",
 830       "xxxx 1 17 x g x False\n",
 831       "xxxx 1 18 x c e False\n",
 832       "xxxx 1 19 x h d False\n",
 833       "xxxx 1 20 x d w False\n",
 834       "seq1 2 0 y ! y True\n",
 835       "xxxx 2 1 y g x False\n",
 836       "xxxx 2 2 y h g False\n",
 837       "xxxx 2 3 y d h False\n",
 838       "xxxx 2 4 y d d False\n",
 839       "xxxx 2 5 y a v False\n",
 840       "xxxx 2 6 y g x False\n",
 841       "xxxx 2 7 y e d False\n",
 842       "xxxx 2 8 y e v False\n",
 843       "xxxx 2 9 y d a False\n",
 844       "xxxx 2 10 y c g False\n",
 845       "xxxx 2 11 y h w False\n",
 846       "xxxx 2 12 y g v False\n",
 847       "xxxx 2 13 y e e False\n",
 848       "xxxx 2 14 y f u False\n",
 849       "xxxx 2 15 y f w False\n",
 850       "xxxx 2 16 y b x False\n",
 851       "xxxx 2 17 y g e False\n",
 852       "xxxx 2 18 y c d False\n",
 853       "xxxx 2 19 y h w False\n",
 854       "xxxx 2 20 y d c False\n",
 855       "seq1 3 0 x ! x True\n",
 856       "seq2 3 1 x g g True\n",
 857       "seq2 3 2 x h h True\n",
 858       "seq2 3 3 x d d True\n",
 859       "xxxx 3 4 x d v False\n",
 860       "xxxx 3 5 x a x False\n",
 861       "xxxx 3 6 x g d False\n",
 862       "xxxx 3 7 x e v False\n",
 863       "xxxx 3 8 x e a False\n",
 864       "xxxx 3 9 x d g False\n",
 865       "xxxx 3 10 x c w False\n",
 866       "xxxx 3 11 x h v False\n",
 867       "xxxx 3 12 x g e False\n",
 868       "xxxx 3 13 x e u False\n",
 869       "xxxx 3 14 x f w False\n",
 870       "xxxx 3 15 x f x False\n",
 871       "xxxx 3 16 x b e False\n",
 872       "xxxx 3 17 x g d False\n",
 873       "xxxx 3 18 x c w False\n",
 874       "xxxx 3 19 x h c False\n",
 875       "xxxx 3 20 x d z False\n",
 876       "seq1 4 0 v ! g False\n",
 877       "xxxx 4 1 v g h False\n",
 878       "xxxx 4 2 v h d False\n",
 879       "seq1 4 3 v d v True\n",
 880       "xxxx 4 4 v d x False\n",
 881       "xxxx 4 5 v a d False\n",
 882       "xxxx 4 6 v g v False\n",
 883       "xxxx 4 7 v e a False\n",
 884       "xxxx 4 8 v e g False\n",
 885       "xxxx 4 9 v d w False\n",
 886       "xxxx 4 10 v c v False\n",
 887       "xxxx 4 11 v h e False\n",
 888       "xxxx 4 12 v g u False\n",
 889       "xxxx 4 13 v e w False\n",
 890       "xxxx 4 14 v f x False\n",
 891       "xxxx 4 15 v f e False\n",
 892       "xxxx 4 16 v b d False\n",
 893       "xxxx 4 17 v g w False\n",
 894       "xxxx 4 18 v c c False\n",
 895       "xxxx 4 19 v h z False\n",
 896       "xxxx 4 20 v d y False\n",
 897       "seq1 5 0 x ! h False\n",
 898       "xxxx 5 1 x g d False\n",
 899       "xxxx 5 2 x h v False\n",
 900       "seq1 5 3 x d x True\n",
 901       "seq2 5 4 x d d True\n",
 902       "xxxx 5 5 x a v False\n",
 903       "xxxx 5 6 x g a False\n",
 904       "xxxx 5 7 x e g False\n",
 905       "xxxx 5 8 x e w False\n",
 906       "xxxx 5 9 x d v False\n",
 907       "xxxx 5 10 x c e False\n",
 908       "xxxx 5 11 x h u False\n",
 909       "xxxx 5 12 x g w False\n",
 910       "xxxx 5 13 x e x False\n",
 911       "xxxx 5 14 x f e False\n",
 912       "xxxx 5 15 x f d False\n",
 913       "xxxx 5 16 x b w False\n",
 914       "xxxx 5 17 x g c False\n",
 915       "xxxx 5 18 x c z False\n",
 916       "xxxx 5 19 x h y False\n",
 917       "xxxx 5 20 x d h False\n",
 918       "seq1 6 0 v ! d False\n",
 919       "xxxx 6 1 v g v False\n",
 920       "xxxx 6 2 v h x False\n",
 921       "xxxx 6 3 v d d False\n",
 922       "seq1 6 4 v d v True\n",
 923       "seq2 6 5 v a a True\n",
 924       "seq2 6 6 v g g True\n",
 925       "xxxx 6 7 v e w False\n",
 926       "xxxx 6 8 v e v False\n",
 927       "xxxx 6 9 v d e False\n",
 928       "xxxx 6 10 v c u False\n",
 929       "xxxx 6 11 v h w False\n",
 930       "xxxx 6 12 v g x False\n",
 931       "xxxx 6 13 v e e False\n",
 932       "xxxx 6 14 v f d False\n",
 933       "xxxx 6 15 v f w False\n",
 934       "xxxx 6 16 v b c False\n",
 935       "xxxx 6 17 v g z False\n",
 936       "xxxx 6 18 v c y False\n",
 937       "xxxx 6 19 v h h False\n",
 938       "xxxx 6 20 v d g False\n",
 939       "seq1 7 0 w ! v False\n",
 940       "xxxx 7 1 w g x False\n",
 941       "xxxx 7 2 w h d False\n",
 942       "xxxx 7 3 w d v False\n",
 943       "xxxx 7 4 w d a False\n",
 944       "xxxx 7 5 w a g False\n",
 945       "seq1 7 6 w g w True\n",
 946       "xxxx 7 7 w e v False\n",
 947       "xxxx 7 8 w e e False\n",
 948       "xxxx 7 9 w d u False\n",
 949       "xxxx 7 10 w c w False\n",
 950       "xxxx 7 11 w h x False\n",
 951       "xxxx 7 12 w g e False\n",
 952       "xxxx 7 13 w e d False\n",
 953       "xxxx 7 14 w f w False\n",
 954       "xxxx 7 15 w f c False\n",
 955       "xxxx 7 16 w b z False\n",
 956       "xxxx 7 17 w g y False\n",
 957       "xxxx 7 18 w c h False\n",
 958       "xxxx 7 19 w h g False\n",
 959       "xxxx 7 20 w d z False\n",
 960       "seq1 8 0 v ! x False\n",
 961       "xxxx 8 1 v g d False\n",
 962       "xxxx 8 2 v h v False\n",
 963       "xxxx 8 3 v d a False\n",
 964       "xxxx 8 4 v d g False\n",
 965       "xxxx 8 5 v a w False\n",
 966       "seq1 8 6 v g v True\n",
 967       "seq2 8 7 v e e True\n",
 968       "xxxx 8 8 v e u False\n",
 969       "xxxx 8 9 v d w False\n",
 970       "xxxx 8 10 v c x False\n",
 971       "xxxx 8 11 v h e False\n",
 972       "xxxx 8 12 v g d False\n",
 973       "xxxx 8 13 v e w False\n",
 974       "xxxx 8 14 v f c False\n",
 975       "xxxx 8 15 v f z False\n",
 976       "xxxx 8 16 v b y False\n",
 977       "xxxx 8 17 v g h False\n",
 978       "xxxx 8 18 v c g False\n",
 979       "xxxx 8 19 v h z False\n",
 980       "xxxx 8 20 v d x False\n",
 981       "seq1 9 0 u ! d False\n",
 982       "xxxx 9 1 u g v False\n",
 983       "xxxx 9 2 u h a False\n",
 984       "xxxx 9 3 u d g False\n",
 985       "xxxx 9 4 u d w False\n",
 986       "xxxx 9 5 u a v False\n",
 987       "xxxx 9 6 u g e False\n",
 988       "seq1 9 7 u e u True\n",
 989       "xxxx 9 8 u e w False\n",
 990       "xxxx 9 9 u d x False\n",
 991       "xxxx 9 10 u c e False\n",
 992       "xxxx 9 11 u h d False\n",
 993       "xxxx 9 12 u g w False\n",
 994       "xxxx 9 13 u e c False\n",
 995       "xxxx 9 14 u f z False\n",
 996       "xxxx 9 15 u f y False\n",
 997       "xxxx 9 16 u b h False\n",
 998       "xxxx 9 17 u g g False\n",
 999       "xxxx 9 18 u c z False\n",
1000       "xxxx 9 19 u h x False\n",
1001       "xxxx 9 20 u d w False\n",
1002       "seq1 10 0 w ! v False\n",
1003       "xxxx 10 1 w g a False\n",
1004       "xxxx 10 2 w h g False\n",
1005       "xxxx 10 3 w d w False\n",
1006       "xxxx 10 4 w d v False\n",
1007       "xxxx 10 5 w a e False\n",
1008       "xxxx 10 6 w g u False\n",
1009       "seq1 10 7 w e w True\n",
1010       "xxxx 10 8 w e x False\n",
1011       "xxxx 10 9 w d e False\n",
1012       "xxxx 10 10 w c d False\n",
1013       "xxxx 10 11 w h w False\n",
1014       "xxxx 10 12 w g c False\n",
1015       "xxxx 10 13 w e z False\n",
1016       "xxxx 10 14 w f y False\n",
1017       "xxxx 10 15 w f h False\n",
1018       "xxxx 10 16 w b g False\n",
1019       "xxxx 10 17 w g z False\n",
1020       "xxxx 10 18 w c x False\n",
1021       "xxxx 10 19 w h w False\n",
1022       "xxxx 10 20 w d e False\n",
1023       "seq1 11 0 x ! a False\n",
1024       "xxxx 11 1 x g g False\n",
1025       "xxxx 11 2 x h w False\n",
1026       "xxxx 11 3 x d v False\n",
1027       "xxxx 11 4 x d e False\n",
1028       "xxxx 11 5 x a u False\n",
1029       "xxxx 11 6 x g w False\n",
1030       "seq1 11 7 x e x True\n",
1031       "seq2 11 8 x e e True\n",
1032       "seq2 11 9 x d d True\n",
1033       "xxxx 11 10 x c w False\n",
1034       "xxxx 11 11 x h c False\n",
1035       "xxxx 11 12 x g z False\n",
1036       "xxxx 11 13 x e y False\n",
1037       "xxxx 11 14 x f h False\n",
1038       "xxxx 11 15 x f g False\n",
1039       "xxxx 11 16 x b z False\n",
1040       "xxxx 11 17 x g x False\n",
1041       "xxxx 11 18 x c w False\n",
1042       "xxxx 11 19 x h e False\n",
1043       "xxxx 11 20 x d w False\n",
1044       "seq1 12 0 w ! g False\n",
1045       "xxxx 12 1 w g w False\n",
1046       "xxxx 12 2 w h v False\n",
1047       "xxxx 12 3 w d e False\n",
1048       "xxxx 12 4 w d u False\n",
1049       "xxxx 12 5 w a w False\n",
1050       "xxxx 12 6 w g x False\n",
1051       "xxxx 12 7 w e e False\n",
1052       "xxxx 12 8 w e d False\n",
1053       "seq1 12 9 w d w True\n",
1054       "seq2 12 10 w c c True\n",
1055       "xxxx 12 11 w h z False\n",
1056       "xxxx 12 12 w g y False\n",
1057       "xxxx 12 13 w e h False\n",
1058       "xxxx 12 14 w f g False\n",
1059       "xxxx 12 15 w f z False\n",
1060       "xxxx 12 16 w b x False\n",
1061       "xxxx 12 17 w g w False\n",
1062       "xxxx 12 18 w c e False\n",
1063       "xxxx 12 19 w h w False\n",
1064       "xxxx 12 20 w d f False\n",
1065       "seq1 13 0 z ! w False\n",
1066       "xxxx 13 1 z g v False\n",
1067       "xxxx 13 2 z h e False\n",
1068       "xxxx 13 3 z d u False\n",
1069       "xxxx 13 4 z d w False\n",
1070       "xxxx 13 5 z a x False\n",
1071       "xxxx 13 6 z g e False\n",
1072       "xxxx 13 7 z e d False\n",
1073       "xxxx 13 8 z e w False\n",
1074       "xxxx 13 9 z d c False\n",
1075       "seq1 13 10 z c z True\n",
1076       "xxxx 13 11 z h y False\n",
1077       "xxxx 13 12 z g h False\n",
1078       "xxxx 13 13 z e g False\n",
1079       "xxxx 13 14 z f z False\n",
1080       "xxxx 13 15 z f x False\n",
1081       "xxxx 13 16 z b w False\n",
1082       "xxxx 13 17 z g e False\n",
1083       "xxxx 13 18 z c w False\n",
1084       "xxxx 13 19 z h f False\n",
1085       "xxxx 13 20 z d z False\n",
1086       "seq1 14 0 y ! v False\n",
1087       "xxxx 14 1 y g e False\n",
1088       "xxxx 14 2 y h u False\n",
1089       "xxxx 14 3 y d w False\n",
1090       "xxxx 14 4 y d x False\n",
1091       "xxxx 14 5 y a e False\n",
1092       "xxxx 14 6 y g d False\n",
1093       "xxxx 14 7 y e w False\n",
1094       "xxxx 14 8 y e c False\n",
1095       "xxxx 14 9 y d z False\n",
1096       "seq1 14 10 y c y True\n",
1097       "seq2 14 11 y h h True\n",
1098       "seq2 14 12 y g g True\n",
1099       "xxxx 14 13 y e z False\n",
1100       "xxxx 14 14 y f x False\n",
1101       "xxxx 14 15 y f w False\n",
1102       "xxxx 14 16 y b e False\n",
1103       "xxxx 14 17 y g w False\n",
1104       "xxxx 14 18 y c f False\n",
1105       "xxxx 14 19 y h z False\n",
1106       "xxxx 14 20 y d f False\n",
1107       "seq1 15 0 z ! e False\n",
1108       "xxxx 15 1 z g u False\n",
1109       "xxxx 15 2 z h w False\n",
1110       "xxxx 15 3 z d x False\n",
1111       "xxxx 15 4 z d e False\n",
1112       "xxxx 15 5 z a d False\n",
1113       "xxxx 15 6 z g w False\n",
1114       "xxxx 15 7 z e c False\n",
1115       "xxxx 15 8 z e z False\n",
1116       "xxxx 15 9 z d y False\n",
1117       "xxxx 15 10 z c h False\n",
1118       "xxxx 15 11 z h g False\n",
1119       "seq1 15 12 z g z True\n",
1120       "xxxx 15 13 z e x False\n",
1121       "xxxx 15 14 z f w False\n",
1122       "xxxx 15 15 z f e False\n",
1123       "xxxx 15 16 z b w False\n",
1124       "xxxx 15 17 z g f False\n",
1125       "xxxx 15 18 z c z False\n",
1126       "xxxx 15 19 z h f False\n",
1127       "xxxx 15 20 z d b False\n",
1128       "seq1 16 0 x ! u False\n",
1129       "xxxx 16 1 x g w False\n",
1130       "xxxx 16 2 x h x False\n",
1131       "xxxx 16 3 x d e False\n",
1132       "xxxx 16 4 x d d False\n",
1133       "xxxx 16 5 x a w False\n",
1134       "xxxx 16 6 x g c False\n",
1135       "xxxx 16 7 x e z False\n",
1136       "xxxx 16 8 x e y False\n",
1137       "xxxx 16 9 x d h False\n",
1138       "xxxx 16 10 x c g False\n",
1139       "xxxx 16 11 x h z False\n",
1140       "seq1 16 12 x g x True\n",
1141       "xxxx 16 13 x e w False\n",
1142       "xxxx 16 14 x f e False\n",
1143       "xxxx 16 15 x f w False\n",
1144       "xxxx 16 16 x b f False\n",
1145       "xxxx 16 17 x g z False\n",
1146       "xxxx 16 18 x c f False\n",
1147       "xxxx 16 19 x h b False\n",
1148       "xxxx 16 20 x d u False\n",
1149       "seq1 17 0 w ! w False\n",
1150       "xxxx 17 1 w g x False\n",
1151       "xxxx 17 2 w h e False\n",
1152       "xxxx 17 3 w d d False\n",
1153       "xxxx 17 4 w d w False\n",
1154       "xxxx 17 5 w a c False\n",
1155       "xxxx 17 6 w g z False\n",
1156       "xxxx 17 7 w e y False\n",
1157       "xxxx 17 8 w e h False\n",
1158       "xxxx 17 9 w d g False\n",
1159       "xxxx 17 10 w c z False\n",
1160       "xxxx 17 11 w h x False\n",
1161       "seq1 17 12 w g w True\n",
1162       "seq2 17 13 w e e True\n",
1163       "xxxx 17 14 w f w False\n",
1164       "xxxx 17 15 w f f False\n",
1165       "xxxx 17 16 w b z False\n",
1166       "xxxx 17 17 w g f False\n",
1167       "xxxx 17 18 w c b False\n",
1168       "xxxx 17 19 w h u False\n",
1169       "xxxx 17 20 w d g False\n",
1170       "seq1 18 0 w ! x False\n",
1171       "xxxx 18 1 w g e False\n",
1172       "xxxx 18 2 w h d False\n",
1173       "xxxx 18 3 w d w False\n",
1174       "xxxx 18 4 w d c False\n",
1175       "xxxx 18 5 w a z False\n",
1176       "xxxx 18 6 w g y False\n",
1177       "xxxx 18 7 w e h False\n",
1178       "xxxx 18 8 w e g False\n",
1179       "xxxx 18 9 w d z False\n",
1180       "xxxx 18 10 w c x False\n",
1181       "xxxx 18 11 w h w False\n",
1182       "xxxx 18 12 w g e False\n",
1183       "seq1 18 13 w e w True\n",
1184       "seq2 18 14 w f f True\n",
1185       "xxxx 18 15 w f z False\n",
1186       "xxxx 18 16 w b f False\n",
1187       "xxxx 18 17 w g b False\n",
1188       "xxxx 18 18 w c u False\n",
1189       "xxxx 18 19 w h g False\n",
1190       "xxxx 18 20 w d c False\n",
1191       "seq1 19 0 z ! e False\n",
1192       "xxxx 19 1 z g d False\n",
1193       "xxxx 19 2 z h w False\n",
1194       "xxxx 19 3 z d c False\n",
1195       "xxxx 19 4 z d z False\n",
1196       "xxxx 19 5 z a y False\n",
1197       "xxxx 19 6 z g h False\n",
1198       "xxxx 19 7 z e g False\n",
1199       "xxxx 19 8 z e z False\n",
1200       "xxxx 19 9 z d x False\n",
1201       "xxxx 19 10 z c w False\n",
1202       "xxxx 19 11 z h e False\n",
1203       "xxxx 19 12 z g w False\n",
1204       "xxxx 19 13 z e f False\n",
1205       "seq1 19 14 z f z True\n",
1206       "seq2 19 15 z f f True\n",
1207       "seq2 19 16 z b b True\n",
1208       "xxxx 19 17 z g u False\n",
1209       "xxxx 19 18 z c g False\n",
1210       "xxxx 19 19 z h c False\n",
1211       "xxxx 19 20 z d h False\n",
1212       "seq1 20 0 u ! d False\n",
1213       "xxxx 20 1 u g w False\n",
1214       "xxxx 20 2 u h c False\n",
1215       "xxxx 20 3 u d z False\n",
1216       "xxxx 20 4 u d y False\n",
1217       "xxxx 20 5 u a h False\n",
1218       "xxxx 20 6 u g g False\n",
1219       "xxxx 20 7 u e z False\n",
1220       "xxxx 20 8 u e x False\n",
1221       "xxxx 20 9 u d w False\n",
1222       "xxxx 20 10 u c e False\n",
1223       "xxxx 20 11 u h w False\n",
1224       "xxxx 20 12 u g f False\n",
1225       "xxxx 20 13 u e z False\n",
1226       "xxxx 20 14 u f f False\n",
1227       "xxxx 20 15 u f b False\n",
1228       "seq1 20 16 u b u True\n",
1229       "seq2 20 17 u g g True\n",
1230       "seq2 20 18 u c c True\n",
1231       "seq2 20 19 u h h True\n",
1232       "seq2 20 20 u d d True\n",
1233       "T . . . . . . . . . . . . . . . . . . . .\n",
1234       "T . . . . . . . . . . . . . . . . . . . .\n",
1235       "T . . . . . . . . . . . . . . . . . . . .\n",
1236       "T T T T . . . . . . . . . . . . . . . . .\n",
1237       ". . . T . . . . . . . . . . . . . . . . .\n",
1238       ". . . T T . . . . . . . . . . . . . . . .\n",
1239       ". . . . T T T . . . . . . . . . . . . . .\n",
1240       ". . . . . . T . . . . . . . . . . . . . .\n",
1241       ". . . . . . T T . . . . . . . . . . . . .\n",
1242       ". . . . . . . T . . . . . . . . . . . . .\n",
1243       ". . . . . . . T . . . . . . . . . . . . .\n",
1244       ". . . . . . . T T T . . . . . . . . . . .\n",
1245       ". . . . . . . . . T T . . . . . . . . . .\n",
1246       ". . . . . . . . . . T . . . . . . . . . .\n",
1247       ". . . . . . . . . . T T T . . . . . . . .\n",
1248       ". . . . . . . . . . . . T . . . . . . . .\n",
1249       ". . . . . . . . . . . . T . . . . . . . .\n",
1250       ". . . . . . . . . . . . T T . . . . . . .\n",
1251       ". . . . . . . . . . . . . T T . . . . . .\n",
1252       ". . . . . . . . . . . . . . T T T . . . .\n",
1253       ". . . . . . . . . . . . . . . . T T T T T\n"
1254      ]
1255     }
1256    ],
1257    "source": [
1258     "v, bp, t = is_interleave(s2, s1, il, return_backpointers=True, return_table=True, debug=True)\n",
1259     "print(show_table(t))"
1260    ]
1261   },
1262   {
1263    "cell_type": "code",
1264    "execution_count": 23,
1265    "metadata": {},
1266    "outputs": [
1267     {
1268      "data": {
1269       "text/plain": [
1270        "'XYXghdVXdVagWVeUWXedWcZYhgZXWeWfZfbUgchd'"
1271       ]
1272      },
1273      "execution_count": 23,
1274      "metadata": {},
1275      "output_type": "execute_result"
1276     }
1277    ],
1278    "source": [
1279     "show_backtrace(bp)"
1280    ]
1281   },
1282   {
1283    "cell_type": "code",
1284    "execution_count": 24,
1285    "metadata": {},
1286    "outputs": [
1287     {
1288      "name": "stdout",
1289      "output_type": "stream",
1290      "text": [
1291       "T . . . . . . . . . . . . . . . . . . . .\n",
1292       "T . . . . . . . . . . . . . . . . . . . .\n",
1293       "T . . . . . . . . . . . . . . . . . . . .\n",
1294       "T T T T . . . . . . . . . . . . . . . . .\n",
1295       ". . . T . . . . . . . . . . . . . . . . .\n",
1296       ". . . T T . . . . . . . . . . . . . . . .\n",
1297       ". . . . T T T . . . . . . . . . . . . . .\n",
1298       ". . . . . . T . . . . . . . . . . . . . .\n",
1299       ". . . . . . T T . . . . . . . . . . . . .\n",
1300       ". . . . . . . T . . . . . . . . . . . . .\n",
1301       ". . . . . . . T . . . . . . . . . . . . .\n",
1302       ". . . . . . . T T T . . . . . . . . . . .\n",
1303       ". . . . . . . . . T T . . . . . . . . . .\n",
1304       ". . . . . . . . . . T . . . . . . . . . .\n",
1305       ". . . . . . . . . . T T T . . . . . . . .\n",
1306       ". . . . . . . . . . . . T . . . . . . . .\n",
1307       ". . . . . . . . . . . . T . . . . . . . .\n",
1308       ". . . . . . . . . . . . T T . . . . . . .\n",
1309       ". . . . . . . . . . . . . T T . . . . . .\n",
1310       ". . . . . . . . . . . . . . T T T . . . .\n",
1311       ". . . . . . . . . . . . . . . . T T T T T\n",
1312       "XYXghdVXdVagWVeUWXedWcZYhgZXWeWfZfbUgchd\n"
1313      ]
1314     },
1315     {
1316      "data": {
1317       "text/plain": [
1318        "True"
1319       ]
1320      },
1321      "execution_count": 24,
1322      "metadata": {},
1323      "output_type": "execute_result"
1324     }
1325    ],
1326    "source": [
1327     "v, bp, t = is_interleave(s2, s1, il, return_backpointers=True, return_table=True)\n",
1328     "print(show_table(t))\n",
1329     "print(show_backtrace(bp))\n",
1330     "v"
1331    ]
1332   },
1333   {
1334    "cell_type": "code",
1335    "execution_count": 25,
1336    "metadata": {},
1337    "outputs": [
1338     {
1339      "data": {
1340       "text/plain": [
1341        "('fahfgbdechbafcbcadcfchhccffhfgeagdhdceebccbhgdefgd',\n",
1342        " 'badbgfaachhhhgghhebahhcbgabcfafeehfcabhbaaccgbcfae',\n",
1343        " 'badfbgfahfgbadecahcbahfhchbchagghhdcefchbahhhcbcgacfbcffhafefgeaegdhfcabhhbdcaaccgebcfebcaecbhgdefgd',\n",
1344        " 100)"
1345       ]
1346      },
1347      "execution_count": 25,
1348      "metadata": {},
1349      "output_type": "execute_result"
1350     }
1351    ],
1352    "source": [
1353     "s1 = make_string(50)\n",
1354     "s2 = make_string(50)\n",
1355     "il = interleave(s1, s2)\n",
1356     "s1, s2, il, len(il)"
1357    ]
1358   },
1359   {
1360    "cell_type": "code",
1361    "execution_count": 26,
1362    "metadata": {},
1363    "outputs": [
1364     {
1365      "name": "stdout",
1366      "output_type": "stream",
1367      "text": [
1368       "T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1369       "T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1370       "T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1371       "T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1372       ". T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1373       ". T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1374       ". T T T T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1375       ". T . . . . T T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1376       ". . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1377       ". . . . . . . . . . T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1378       ". . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1379       ". . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1380       ". . . . . . . . . . . . . . T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1381       ". . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1382       ". . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1383       ". . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1384       ". . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1385       ". . . . . . . . . . . . . . . . . T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1386       ". . . . . . . . . . . . . . . . . . . T T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1387       ". . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1388       ". . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1389       ". . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1390       ". . . . . . . . . . . . . . . . . . . . . . T T T . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1391       ". . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1392       ". . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1393       ". . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1394       ". . . . . . . . . . . . . . . . . . . . . . . . T T T . . . . . . . . . . . . . . . . . . . . . . . .\n",
1395       ". . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . .\n",
1396       ". . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . .\n",
1397       ". . . . . . . . . . . . . . . . . . . . . . . . . . T T T . . . . . . . . . . . . . . . . . . . . . .\n",
1398       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . .\n",
1399       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . .\n",
1400       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T T T . . . . . . . . . . . . . . . . . .\n",
1401       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . T T T T . . . . . . . . . . . . . . .\n",
1402       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . .\n",
1403       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . .\n",
1404       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . .\n",
1405       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . .\n",
1406       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . .\n",
1407       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . .\n",
1408       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T . . . . . . . . . . . . .\n",
1409       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . .\n",
1410       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . .\n",
1411       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . .\n",
1412       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . .\n",
1413       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . .\n",
1414       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . .\n",
1415       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . .\n",
1416       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T T . . . . . . . . .\n",
1417       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . .\n",
1418       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T T T T T T T T\n",
1419       "BADfBGFahfgbAdecAhCbaHfHcHbcHaGGHHdcEfchBAhHHCBcGAcfBCfFhAFEfgeaEgdHFCABhHBdcAACCGeBCFebcAEcbhgdefgd\n"
1420      ]
1421     },
1422     {
1423      "data": {
1424       "text/plain": [
1425        "True"
1426       ]
1427      },
1428      "execution_count": 26,
1429      "metadata": {},
1430      "output_type": "execute_result"
1431     }
1432    ],
1433    "source": [
1434     "v, bp, t = is_interleave(s2, s1, il, return_backpointers=True, return_table=True)\n",
1435     "print(show_table(t))\n",
1436     "print(show_backtrace(bp))\n",
1437     "v"
1438    ]
1439   },
1440   {
1441    "cell_type": "code",
1442    "execution_count": 27,
1443    "metadata": {},
1444    "outputs": [
1445     {
1446      "name": "stdout",
1447      "output_type": "stream",
1448      "text": [
1449       "1000 loops, best of 3: 1.24 ms per loop\n"
1450      ]
1451     }
1452    ],
1453    "source": [
1454     "%%timeit\n",
1455     "is_interleave(s2, s1, il)"
1456    ]
1457   },
1458   {
1459    "cell_type": "code",
1460    "execution_count": 28,
1461    "metadata": {},
1462    "outputs": [
1463     {
1464      "name": "stdout",
1465      "output_type": "stream",
1466      "text": [
1467       "T T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1468       ". . . T T T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1469       ". . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1470       ". . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1471       ". . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1472       ". . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1473       ". . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1474       ". . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1475       ". . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1476       ". . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1477       ". . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1478       ". . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1479       ". . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1480       ". . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1481       ". . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1482       ". . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1483       ". . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1484       ". . . . . . . . . . . . . T T T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1485       ". . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1486       ". . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1487       ". . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1488       ". . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1489       ". . . . . . . . . . . . . . . . . . T T T T T . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1490       ". . . . . . . . . . . . . . . . . . . . T T T T T . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1491       ". . . . . . . . . . . . . . . . . . . . . . T . T T T . . . . . . . . . . . . . . . . . . . . . . . .\n",
1492       ". . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . . . . . . . .\n",
1493       ". . . . . . . . . . . . . . . . . . . . . . . . . . T T T T . . . . . . . . . . . . . . . . . . . . .\n",
1494       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . . . . . .\n",
1495       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T T . . . . . . . . . . . . . . . . . .\n",
1496       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . T . . . . . . . . . . . . . . . . . .\n",
1497       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . .\n",
1498       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . . .\n",
1499       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T . . . . . . . . . . . . . . . . .\n",
1500       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . . . . . . . . .\n",
1501       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T T T T T . . . . . . . . . . .\n",
1502       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . T T T . . . . . . . . . .\n",
1503       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . . . . . . . . . .\n",
1504       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T T T T . . . . .\n",
1505       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T T . .\n",
1506       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . .\n",
1507       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T . .\n",
1508       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T T T\n",
1509       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1510       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1511       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1512       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1513       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1514       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1515       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1516       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1517       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T\n",
1518       "badFbgfAHFGBaDECaHcBAhFhChBChAgghhDCeFCHbahhHcbCgaCFbcfFHafeFGEAeGDhfcabhHbDCaaccgEbcfEBCaeCBHGDEFGD\n"
1519      ]
1520     },
1521     {
1522      "data": {
1523       "text/plain": [
1524        "True"
1525       ]
1526      },
1527      "execution_count": 28,
1528      "metadata": {},
1529      "output_type": "execute_result"
1530     }
1531    ],
1532    "source": [
1533     "v, bp, t = is_interleave(s1, s2, il, return_backpointers=True, return_table=True)\n",
1534     "print(show_table(t))\n",
1535     "print(show_backtrace(bp))\n",
1536     "v"
1537    ]
1538   },
1539   {
1540    "cell_type": "code",
1541    "execution_count": 29,
1542    "metadata": {},
1543    "outputs": [
1544     {
1545      "data": {
1546       "text/plain": [
1547        "True"
1548       ]
1549      },
1550      "execution_count": 29,
1551      "metadata": {},
1552      "output_type": "execute_result"
1553     }
1554    ],
1555    "source": [
1556     "show_backtrace(bp).lower() == il"
1557    ]
1558   },
1559   {
1560    "cell_type": "code",
1561    "execution_count": 30,
1562    "metadata": {},
1563    "outputs": [
1564     {
1565      "data": {
1566       "text/plain": [
1567        "('gbaehdacgdebgaebecfbefcbehfgcheaccdehbfdfadebhcehd', False, False)"
1568       ]
1569      },
1570      "execution_count": 30,
1571      "metadata": {},
1572      "output_type": "execute_result"
1573     }
1574    ],
1575    "source": [
1576     "s3 = make_string(50)\n",
1577     "s3, is_interleave(s1, s3, il), is_interleave(s2, s3, il)"
1578    ]
1579   },
1580   {
1581    "cell_type": "code",
1582    "execution_count": 31,
1583    "metadata": {},
1584    "outputs": [
1585     {
1586      "name": "stdout",
1587      "output_type": "stream",
1588      "text": [
1589       "T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1590       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1591       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1592       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1593       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1594       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1595       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1596       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1597       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1598       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1599       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1600       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1601       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1602       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1603       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1604       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1605       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1606       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1607       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1608       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1609       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1610       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1611       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1612       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1613       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1614       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1615       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1616       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1617       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1618       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1619       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1620       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1621       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1622       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1623       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1624       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1625       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1626       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1627       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1628       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1629       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1630       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1631       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1632       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1633       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1634       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1635       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1636       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1637       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1638       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1639       ". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .\n",
1640       "\n"
1641      ]
1642     },
1643     {
1644      "data": {
1645       "text/plain": [
1646        "False"
1647       ]
1648      },
1649      "execution_count": 31,
1650      "metadata": {},
1651      "output_type": "execute_result"
1652     }
1653    ],
1654    "source": [
1655     "v, bp, t = is_interleave(s1, s3, il, return_backpointers=True, return_table=True)\n",
1656     "print(show_table(t))\n",
1657     "print(show_backtrace(bp))\n",
1658     "v"
1659    ]
1660   },
1661   {
1662    "cell_type": "code",
1663    "execution_count": 32,
1664    "metadata": {
1665     "collapsed": true
1666    },
1667    "outputs": [],
1668    "source": [
1669     "def is_interleave_recursive(s1, s2, s3):\n",
1670     "    if not s1:\n",
1671     "        return s2 == s3\n",
1672     "    elif not s2:\n",
1673     "        return s1 == s3\n",
1674     "    else:\n",
1675     "        if s1[-1] == s2[-1] and s1[-1] == s3[-1]:\n",
1676     "            return is_interleave_recursive(s1[:-1], s2, s3[:-1]) or is_interleave(s1, s2[:-1], s3[:-1])\n",
1677     "        elif s1[-1] == s3[-1]:\n",
1678     "            return is_interleave_recursive(s1[:-1], s2, s3[:-1])\n",
1679     "        elif s2[-1] == s3[-1]:\n",
1680     "            return is_interleave(s1, s2[:-1], s3[:-1])\n",
1681     "        else:\n",
1682     "            return False"
1683    ]
1684   },
1685   {
1686    "cell_type": "code",
1687    "execution_count": 33,
1688    "metadata": {
1689     "collapsed": true
1690    },
1691    "outputs": [],
1692    "source": [
1693     "s1 = make_string(500)\n",
1694     "s2 = make_string(500)\n",
1695     "s3 = make_string(500)\n",
1696     "s12 = interleave(s1, s2)\n",
1697     "s23 = interleave(s2, s3)"
1698    ]
1699   },
1700   {
1701    "cell_type": "code",
1702    "execution_count": 34,
1703    "metadata": {},
1704    "outputs": [
1705     {
1706      "data": {
1707       "text/plain": [
1708        "True"
1709       ]
1710      },
1711      "execution_count": 34,
1712      "metadata": {},
1713      "output_type": "execute_result"
1714     }
1715    ],
1716    "source": [
1717     "is_interleave_recursive(s1, s2, s12)"
1718    ]
1719   },
1720   {
1721    "cell_type": "code",
1722    "execution_count": 35,
1723    "metadata": {},
1724    "outputs": [
1725     {
1726      "data": {
1727       "text/plain": [
1728        "False"
1729       ]
1730      },
1731      "execution_count": 35,
1732      "metadata": {},
1733      "output_type": "execute_result"
1734     }
1735    ],
1736    "source": [
1737     "is_interleave_recursive(s1, s2, s23)"
1738    ]
1739   },
1740   {
1741    "cell_type": "markdown",
1742    "metadata": {},
1743    "source": [
1744     "## Example"
1745    ]
1746   },
1747   {
1748    "cell_type": "code",
1749    "execution_count": 36,
1750    "metadata": {
1751     "collapsed": true
1752    },
1753    "outputs": [],
1754    "source": [
1755     "def show_annotated_table(table, bps):\n",
1756     "    return '\\n'.join(' '.join('*' if (i, j) == (0, 0) else bps[i, j][2] if table[i, j] else '.' for j in sorted(set([k[1] for k in table])))\n",
1757     "        for i in sorted(set([k[0] for k in table])))"
1758    ]
1759   },
1760   {
1761    "cell_type": "code",
1762    "execution_count": 37,
1763    "metadata": {
1764     "collapsed": true
1765    },
1766    "outputs": [],
1767    "source": [
1768     "def show_backtrace_star(bps):\n",
1769     "    i = max([0] + [k[0] for k in bps])\n",
1770     "    j = max([0] + [k[1] for k in bps])\n",
1771     "    chars = ''\n",
1772     "    stars = ''\n",
1773     "    if (i, j) in bps:\n",
1774     "        while i != 0 or j != 0:\n",
1775     "            chars += bps[i, j][2]\n",
1776     "            if bps[i, j][3] == 'seq1':\n",
1777     "                stars += '*'\n",
1778     "            else:\n",
1779     "                stars += ' '\n",
1780     "            i, j = bps[i, j][0], bps[i, j][1] \n",
1781     "        return ''.join(list(reversed(chars))) + '\\n' + ''.join(list(reversed(stars)))\n",
1782     "    else:\n",
1783     "        return ''"
1784    ]
1785   },
1786   {
1787    "cell_type": "code",
1788    "execution_count": 73,
1789    "metadata": {},
1790    "outputs": [
1791     {
1792      "name": "stdout",
1793      "output_type": "stream",
1794      "text": [
1795       "0: accbadaadc\n",
1796       "1: bbbbaabada\n",
1797       "2: cdaacacadcddbccacdab\n",
1798       "3: bbcdabbaaabcbcadcaac\n",
1799       "4: accbbabbdbaaabadaadc\n",
1800       "5: acadcdddab\n",
1801       "6: aacccabaddcdaddaabdc\n"
1802      ]
1803     },
1804     {
1805      "data": {
1806       "text/plain": [
1807        "['accbbabbdbaaabadaadc']"
1808       ]
1809      },
1810      "execution_count": 73,
1811      "metadata": {},
1812      "output_type": "execute_result"
1813     }
1814    ],
1815    "source": [
1816     "s1 = make_string(10, alphabet='abcd')\n",
1817     "s2 = make_string(10, alphabet='abcd')\n",
1818     "s3 = make_string(10, alphabet='abcd')\n",
1819     "s4 = make_string(10, alphabet='abcd')\n",
1820     "il = interleave(s1, s2)\n",
1821     "bs = [s3, il, interleave(s3, s4), interleave(s2, s4), interleave(s1, s3)]\n",
1822     "random.shuffle(bs)\n",
1823     "bs = [s1, s2] + bs\n",
1824     "tg = [l for l in bs if is_interleave(s1, s2, l)]\n",
1825     "print('\\n'.join(['{}: {}'.format(i, s) for i, s in enumerate(bs)]))\n",
1826     "tg"
1827    ]
1828   },
1829   {
1830    "cell_type": "code",
1831    "execution_count": 74,
1832    "metadata": {},
1833    "outputs": [
1834     {
1835      "name": "stdout",
1836      "output_type": "stream",
1837      "text": [
1838       "* . . . . . . . . . .\n",
1839       "a . . . . . . . . . .\n",
1840       "c . . . . . . . . . .\n",
1841       "c b b . . . . . . . .\n",
1842       "b b . . . . . . . . .\n",
1843       ". a b b . . . . . . .\n",
1844       ". . . d b a a . . . .\n",
1845       ". . . . a a a b a d a\n",
1846       ". . . . a a . a . a a\n",
1847       ". . . . . . . d a . d\n",
1848       ". . . . . . . . . . c\n",
1849       "ACCbBAbbDbaaAbadaADC\n",
1850       "accbbabbdbaaabadaadc\n",
1851       "*** **  *   *    ***\n"
1852      ]
1853     },
1854     {
1855      "data": {
1856       "text/plain": [
1857        "True"
1858       ]
1859      },
1860      "execution_count": 74,
1861      "metadata": {},
1862      "output_type": "execute_result"
1863     }
1864    ],
1865    "source": [
1866     "v, bp, t = is_interleave(s1, s2, il, return_backpointers=True, return_table=True)\n",
1867     "print(show_annotated_table(t, bp))\n",
1868     "print(show_backtrace(bp))\n",
1869     "print(show_backtrace_star(bp))\n",
1870     "v"
1871    ]
1872   },
1873   {
1874    "cell_type": "code",
1875    "execution_count": 75,
1876    "metadata": {},
1877    "outputs": [
1878     {
1879      "name": "stdout",
1880      "output_type": "stream",
1881      "text": [
1882       "aacccabaddcdaddaabdc\n",
1883       " * ** ** *  *   * **\n"
1884      ]
1885     },
1886     {
1887      "data": {
1888       "text/plain": [
1889        "6"
1890       ]
1891      },
1892      "execution_count": 75,
1893      "metadata": {},
1894      "output_type": "execute_result"
1895     }
1896    ],
1897    "source": [
1898     "ind = [i for i, b in enumerate(bs) if is_interleave(s1, s3, b)][0]\n",
1899     "v, bp = is_interleave(s1, s3, bs[ind], return_backpointers=True)\n",
1900     "print(show_backtrace_star(bp))\n",
1901     "ind"
1902    ]
1903   },
1904   {
1905    "cell_type": "code",
1906    "execution_count": 39,
1907    "metadata": {},
1908    "outputs": [
1909     {
1910      "name": "stdout",
1911      "output_type": "stream",
1912      "text": [
1913       "* . . . . . . . . . .\n",
1914       "b d . . . . . . . . .\n",
1915       ". b c c . . . . . . .\n",
1916       ". . . d . . . . . . .\n",
1917       ". . . c a a . . . . .\n",
1918       ". . . a a a . . . . .\n",
1919       ". . . a a a d a . . .\n",
1920       ". . . a a . a a b a c\n",
1921       ". . . . d a . . . . d\n",
1922       ". . . . . . . . . . d\n",
1923       ". . . . . . . . . . c\n",
1924       "BdBccDCaaAAdaAbacDDC\n",
1925       "bdbccdcaaaadaabacddc\n",
1926       "* *  **  **  *   ***\n"
1927      ]
1928     },
1929     {
1930      "data": {
1931       "text/plain": [
1932        "True"
1933       ]
1934      },
1935      "execution_count": 39,
1936      "metadata": {},
1937      "output_type": "execute_result"
1938     }
1939    ],
1940    "source": [
1941     "v, bp, t = is_interleave(s2, s1, il, return_backpointers=True, return_table=True)\n",
1942     "print(show_annotated_table(t, bp))\n",
1943     "print(show_backtrace(bp))\n",
1944     "print(show_backtrace_star(bp))\n",
1945     "v"
1946    ]
1947   },
1948   {
1949    "cell_type": "code",
1950    "execution_count": 40,
1951    "metadata": {},
1952    "outputs": [
1953     {
1954      "name": "stdout",
1955      "output_type": "stream",
1956      "text": [
1957       "* . . . . . . . . . .\n",
1958       ". . . . . . . . . . .\n",
1959       ". . . . . . . . . . .\n",
1960       ". . . . . . . . . . .\n",
1961       ". . . . . . . . . . .\n",
1962       ". . . . . . . . . . .\n",
1963       ". . . . . . . . . . .\n",
1964       ". . . . . . . . . . .\n",
1965       ". . . . . . . . . . .\n",
1966       ". . . . . . . . . . .\n",
1967       ". . . . . . . . . . .\n",
1968       "\n",
1969       "\n"
1970      ]
1971     },
1972     {
1973      "data": {
1974       "text/plain": [
1975        "False"
1976       ]
1977      },
1978      "execution_count": 40,
1979      "metadata": {},
1980      "output_type": "execute_result"
1981     }
1982    ],
1983    "source": [
1984     "v, bp, t = is_interleave(s1, s3, il, return_backpointers=True, return_table=True)\n",
1985     "print(show_annotated_table(t, bp))\n",
1986     "print(show_backtrace(bp))\n",
1987     "print(show_backtrace_star(bp))\n",
1988     "v"
1989    ]
1990   },
1991   {
1992    "cell_type": "code",
1993    "execution_count": 41,
1994    "metadata": {},
1995    "outputs": [
1996     {
1997      "name": "stdout",
1998      "output_type": "stream",
1999      "text": [
2000       "* . . . . . . . . . .\n",
2001       "b . . . . . . . . . .\n",
2002       ". . . . . . . . . . .\n",
2003       ". . . . . . . . . . .\n",
2004       ". . . . . . . . . . .\n",
2005       ". . . . . . . . . . .\n",
2006       ". . . . . . . . . . .\n",
2007       ". . . . . . . . . . .\n",
2008       ". . . . . . . . . . .\n",
2009       ". . . . . . . . . . .\n",
2010       ". . . . . . . . . . .\n",
2011       "B\n",
2012       "b\n",
2013       "*\n"
2014      ]
2015     },
2016     {
2017      "data": {
2018       "text/plain": [
2019        "False"
2020       ]
2021      },
2022      "execution_count": 41,
2023      "metadata": {},
2024      "output_type": "execute_result"
2025     }
2026    ],
2027    "source": [
2028     "v, bp, t = is_interleave(s2, s3, il, return_backpointers=True, return_table=True)\n",
2029     "print(show_annotated_table(t, bp))\n",
2030     "print(show_backtrace(bp))\n",
2031     "print(show_backtrace_star(bp))\n",
2032     "v"
2033    ]
2034   },
2035   {
2036    "cell_type": "markdown",
2037    "metadata": {
2038     "collapsed": true
2039    },
2040    "source": [
2041     "# Make puzzle data"
2042    ]
2043   },
2044   {
2045    "cell_type": "code",
2046    "execution_count": 47,
2047    "metadata": {
2048     "collapsed": true
2049    },
2050    "outputs": [],
2051    "source": [
2052     "my_bill = make_string(200)\n",
2053     "friend_bill = make_string(200)\n",
2054     "other_bills = [make_string(200) for _ in range(98)]\n",
2055     "\n",
2056     "target_interleaved = interleave(my_bill, friend_bill)\n",
2057     "mine_interleaved = [interleave(my_bill, o) for o in random.sample(other_bills, 21)]\n",
2058     "friend_interleaved = [interleave(friend_bill, o) for o in random.sample(other_bills, 13)]\n",
2059     "other_interleaved = []\n",
2060     "for _ in range(103):\n",
2061     "    s1, s2 = random.sample(other_bills, 2)\n",
2062     "    other_interleaved += [interleave(s1, s2)]"
2063    ]
2064   },
2065   {
2066    "cell_type": "code",
2067    "execution_count": 48,
2068    "metadata": {
2069     "collapsed": true
2070    },
2071    "outputs": [],
2072    "source": [
2073     "all_targets = [target_interleaved] + mine_interleaved + friend_interleaved + other_interleaved"
2074    ]
2075   },
2076   {
2077    "cell_type": "code",
2078    "execution_count": 49,
2079    "metadata": {},
2080    "outputs": [
2081     {
2082      "name": "stdout",
2083      "output_type": "stream",
2084      "text": [
2085       "CPU times: user 3.16 s, sys: 8 ms, total: 3.16 s\n",
2086       "Wall time: 3.17 s\n"
2087      ]
2088     },
2089     {
2090      "data": {
2091       "text/plain": [
2092        "[0]"
2093       ]
2094      },
2095      "execution_count": 49,
2096      "metadata": {},
2097      "output_type": "execute_result"
2098     }
2099    ],
2100    "source": [
2101     "%time [i for i, s12 in enumerate(all_targets) if is_interleave(my_bill, friend_bill, s12)]"
2102    ]
2103   },
2104   {
2105    "cell_type": "code",
2106    "execution_count": 50,
2107    "metadata": {},
2108    "outputs": [
2109     {
2110      "name": "stdout",
2111      "output_type": "stream",
2112      "text": [
2113       "CPU times: user 788 ms, sys: 0 ns, total: 788 ms\n",
2114       "Wall time: 789 ms\n"
2115      ]
2116     },
2117     {
2118      "data": {
2119       "text/plain": [
2120        "[0]"
2121       ]
2122      },
2123      "execution_count": 50,
2124      "metadata": {},
2125      "output_type": "execute_result"
2126     }
2127    ],
2128    "source": [
2129     "%time [i for i, s12 in enumerate(all_targets) if is_interleave_recursive(my_bill, friend_bill, s12)]"
2130    ]
2131   },
2132   {
2133    "cell_type": "code",
2134    "execution_count": 51,
2135    "metadata": {
2136     "collapsed": true
2137    },
2138    "outputs": [],
2139    "source": [
2140     "bill_set = all_targets + random.sample(other_bills, 8)\n",
2141     "random.shuffle(bill_set)\n",
2142     "bill_set = [my_bill, friend_bill] + bill_set\n",
2143     "\n",
2144     "# with open('09-bills.txt', 'w') as f:\n",
2145     "#     for i, b in enumerate(bill_set):\n",
2146     "#         f.write('{}: {}\\n'.format(i, b))"
2147    ]
2148   },
2149   {
2150    "cell_type": "code",
2151    "execution_count": null,
2152    "metadata": {
2153     "collapsed": true
2154    },
2155    "outputs": [],
2156    "source": []
2157   }
2158  ],
2159  "metadata": {
2160   "kernelspec": {
2161    "display_name": "Python 3",
2162    "language": "python",
2163    "name": "python3"
2164   },
2165   "language_info": {
2166    "codemirror_mode": {
2167     "name": "ipython",
2168     "version": 3
2169    },
2170    "file_extension": ".py",
2171    "mimetype": "text/x-python",
2172    "name": "python",
2173    "nbconvert_exporter": "python",
2174    "pygments_lexer": "ipython3",
2175    "version": "3.5.2+"
2176   }
2177  },
2178  "nbformat": 4,
2179  "nbformat_minor": 1
2180 }