src/advent03/advent03.ipynb

   1 {
   2  "cells": [
   3   {
   4    "cell_type": "code",
   5    "execution_count": 1,
   6    "metadata": {},
   7    "outputs": [],
   8    "source": [
   9     "{-# LANGUAGE FlexibleContexts #-}\n",
  10     "{-# LANGUAGE MultiWayIf #-}"
  11    ]
  12   },
  13   {
  14    "cell_type": "code",
  15    "execution_count": 2,
  16    "metadata": {},
  17    "outputs": [],
  18    "source": [
  19     "import Data.List (tails)\n",
  20     "import qualified Data.HashMap.Strict as M\n",
  21     "import Data.HashMap.Strict ((!))\n",
  22     "import Control.Monad.State.Lazy"
  23    ]
  24   },
  25   {
  26    "cell_type": "code",
  27    "execution_count": 3,
  28    "metadata": {},
  29    "outputs": [],
  30    "source": [
  31     "offsets2 = repeat 8"
  32    ]
  33   },
  34   {
  35    "cell_type": "code",
  36    "execution_count": 4,
  37    "metadata": {},
  38    "outputs": [
  39     {
  40      "data": {
  41       "text/plain": [
  42        "[8,8,8]"
  43       ]
  44      },
  45      "metadata": {},
  46      "output_type": "display_data"
  47     }
  48    ],
  49    "source": [
  50     "take 3 offsets2"
  51    ]
  52   },
  53   {
  54    "cell_type": "code",
  55    "execution_count": 5,
  56    "metadata": {},
  57    "outputs": [
  58     {
  59      "data": {
  60       "text/plain": [
  61        "[8,16,24]"
  62       ]
  63      },
  64      "metadata": {},
  65      "output_type": "display_data"
  66     }
  67    ],
  68    "source": [
  69     "take 3 $ scanl (+) 8 offsets2"
  70    ]
  71   },
  72   {
  73    "cell_type": "code",
  74    "execution_count": 6,
  75    "metadata": {},
  76    "outputs": [],
  77    "source": [
  78     "diagonal n = scanl (+) 1 $ scanl (+) n $ repeat 8"
  79    ]
  80   },
  81   {
  82    "cell_type": "code",
  83    "execution_count": 7,
  84    "metadata": {},
  85    "outputs": [
  86     {
  87      "data": {
  88       "text/plain": [
  89        "[1,9,25,49,81]"
  90       ]
  91      },
  92      "metadata": {},
  93      "output_type": "display_data"
  94     }
  95    ],
  96    "source": [
  97     "dr = diagonal 8\n",
  98     "take 5 dr"
  99    ]
 100   },
 101   {
 102    "cell_type": "code",
 103    "execution_count": 8,
 104    "metadata": {},
 105    "outputs": [
 106     {
 107      "data": {
 108       "text/plain": [
 109        "[1,5,17,37,65]"
 110       ]
 111      },
 112      "metadata": {},
 113      "output_type": "display_data"
 114     }
 115    ],
 116    "source": [
 117     "ul = diagonal 4\n",
 118     "take 5 ul"
 119    ]
 120   },
 121   {
 122    "cell_type": "code",
 123    "execution_count": 9,
 124    "metadata": {},
 125    "outputs": [
 126     {
 127      "data": {
 128       "text/plain": [
 129        "[1,3,13,31,57]"
 130       ]
 131      },
 132      "metadata": {},
 133      "output_type": "display_data"
 134     }
 135    ],
 136    "source": [
 137     "ur = diagonal 2\n",
 138     "take 5 ur"
 139    ]
 140   },
 141   {
 142    "cell_type": "code",
 143    "execution_count": 10,
 144    "metadata": {},
 145    "outputs": [
 146     {
 147      "data": {
 148       "text/plain": [
 149        "[1,7,21,43,73]"
 150       ]
 151      },
 152      "metadata": {},
 153      "output_type": "display_data"
 154     }
 155    ],
 156    "source": [
 157     "dl = diagonal 6\n",
 158     "take 5 dl"
 159    ]
 160   },
 161   {
 162    "cell_type": "code",
 163    "execution_count": 11,
 164    "metadata": {},
 165    "outputs": [
 166     {
 167      "data": {
 168       "text/plain": [
 169        "73"
 170       ]
 171      },
 172      "metadata": {},
 173      "output_type": "display_data"
 174     }
 175    ],
 176    "source": [
 177     "dl!!4"
 178    ]
 179   },
 180   {
 181    "cell_type": "code",
 182    "execution_count": 12,
 183    "metadata": {},
 184    "outputs": [
 185     {
 186      "data": {
 187       "text/plain": [
 188        "(4,73)"
 189       ]
 190      },
 191      "metadata": {},
 192      "output_type": "display_data"
 193     }
 194    ],
 195    "source": [
 196     "head $ dropWhile ((< 70) . snd) $ zip [0..] dl"
 197    ]
 198   },
 199   {
 200    "cell_type": "code",
 201    "execution_count": 13,
 202    "metadata": {},
 203    "outputs": [
 204     {
 205      "data": {
 206       "text/plain": [
 207        "(4,81)"
 208       ]
 209      },
 210      "metadata": {},
 211      "output_type": "display_data"
 212     }
 213    ],
 214    "source": [
 215     "head $ dropWhile ((< 70) . snd) $ zip [0..] dr"
 216    ]
 217   },
 218   {
 219    "cell_type": "code",
 220    "execution_count": 14,
 221    "metadata": {},
 222    "outputs": [
 223     {
 224      "data": {
 225       "text/plain": [
 226        "[0,1,2]"
 227       ]
 228      },
 229      "metadata": {},
 230      "output_type": "display_data"
 231     }
 232    ],
 233    "source": [
 234     "take 3 [0..]"
 235    ]
 236   },
 237   {
 238    "cell_type": "code",
 239    "execution_count": 15,
 240    "metadata": {},
 241    "outputs": [],
 242    "source": [
 243     "interleave4 (p:ps) (q:qs) (r:rs) (s:ss) = p:q:r:s:interleave4 ps qs rs ss"
 244    ]
 245   },
 246   {
 247    "cell_type": "code",
 248    "execution_count": 16,
 249    "metadata": {},
 250    "outputs": [],
 251    "source": [
 252     "interleave ([]:_) = []\n",
 253     "interleave xss = map head xss ++ interleave (map tail xss)"
 254    ]
 255   },
 256   {
 257    "cell_type": "code",
 258    "execution_count": 17,
 259    "metadata": {},
 260    "outputs": [
 261     {
 262      "data": {
 263       "text/plain": [
 264        "[(0,1),(1,3),(1,5),(1,7),(1,9),(2,13),(2,17),(2,21),(2,25),(3,31),(3,37),(3,43),(3,49),(4,57),(4,65),(4,73),(4,81),(5,91),(5,101),(5,111)]"
 265       ]
 266      },
 267      "metadata": {},
 268      "output_type": "display_data"
 269     }
 270    ],
 271    "source": [
 272     "take 20 $ drop 3 $ interleave4 (zip [0..] ur) (zip [0..] ul) (zip [0..] dl) (zip [0..] dr)"
 273    ]
 274   },
 275   {
 276    "cell_type": "code",
 277    "execution_count": 18,
 278    "metadata": {},
 279    "outputs": [
 280     {
 281      "data": {
 282       "text/plain": [
 283        "[1,1,1,1]"
 284       ]
 285      },
 286      "metadata": {},
 287      "output_type": "display_data"
 288     }
 289    ],
 290    "source": [
 291     "map head [ur, ul, dl, dr]"
 292    ]
 293   },
 294   {
 295    "cell_type": "code",
 296    "execution_count": 19,
 297    "metadata": {},
 298    "outputs": [
 299     {
 300      "data": {
 301       "text/plain": [
 302        "[[3,13],[5,17],[7,21],[9,25]]"
 303       ]
 304      },
 305      "metadata": {},
 306      "output_type": "display_data"
 307     }
 308    ],
 309    "source": [
 310     "map (take 2 . tail) [ur, ul, dl, dr]"
 311    ]
 312   },
 313   {
 314    "cell_type": "code",
 315    "execution_count": 20,
 316    "metadata": {},
 317    "outputs": [
 318     {
 319      "data": {
 320       "text/html": [
 321        "<style>/* Styles used for the Hoogle display in the pager */\n",
 322        ".hoogle-doc {\n",
 323        "display: block;\n",
 324        "padding-bottom: 1.3em;\n",
 325        "padding-left: 0.4em;\n",
 326        "}\n",
 327        ".hoogle-code {\n",
 328        "display: block;\n",
 329        "font-family: monospace;\n",
 330        "white-space: pre;\n",
 331        "}\n",
 332        ".hoogle-text {\n",
 333        "display: block;\n",
 334        "}\n",
 335        ".hoogle-name {\n",
 336        "color: green;\n",
 337        "font-weight: bold;\n",
 338        "}\n",
 339        ".hoogle-head {\n",
 340        "font-weight: bold;\n",
 341        "}\n",
 342        ".hoogle-sub {\n",
 343        "display: block;\n",
 344        "margin-left: 0.4em;\n",
 345        "}\n",
 346        ".hoogle-package {\n",
 347        "font-weight: bold;\n",
 348        "font-style: italic;\n",
 349        "}\n",
 350        ".hoogle-module {\n",
 351        "font-weight: bold;\n",
 352        "}\n",
 353        ".hoogle-class {\n",
 354        "font-weight: bold;\n",
 355        "}\n",
 356        ".get-type {\n",
 357        "color: green;\n",
 358        "font-weight: bold;\n",
 359        "font-family: monospace;\n",
 360        "display: block;\n",
 361        "white-space: pre-wrap;\n",
 362        "}\n",
 363        ".show-type {\n",
 364        "color: green;\n",
 365        "font-weight: bold;\n",
 366        "font-family: monospace;\n",
 367        "margin-left: 1em;\n",
 368        "}\n",
 369        ".mono {\n",
 370        "font-family: monospace;\n",
 371        "display: block;\n",
 372        "}\n",
 373        ".err-msg {\n",
 374        "color: red;\n",
 375        "font-style: italic;\n",
 376        "font-family: monospace;\n",
 377        "white-space: pre;\n",
 378        "display: block;\n",
 379        "}\n",
 380        "#unshowable {\n",
 381        "color: red;\n",
 382        "font-weight: bold;\n",
 383        "}\n",
 384        ".err-msg.in.collapse {\n",
 385        "padding-top: 0.7em;\n",
 386        "}\n",
 387        ".highlight-code {\n",
 388        "white-space: pre;\n",
 389        "font-family: monospace;\n",
 390        "}\n",
 391        ".suggestion-warning { \n",
 392        "font-weight: bold;\n",
 393        "color: rgb(200, 130, 0);\n",
 394        "}\n",
 395        ".suggestion-error { \n",
 396        "font-weight: bold;\n",
 397        "color: red;\n",
 398        "}\n",
 399        ".suggestion-name {\n",
 400        "font-weight: bold;\n",
 401        "}\n",
 402        "</style><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">(map head [ur, ul, dl, dr]) : [[10, 11, 12, 13, 14, 15, 16, 17]]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">map head [ur, ul, dl, dr] : [[10, 11, 12, 13, 14, 15, 16, 17]]</div></div>"
 403       ],
 404       "text/plain": [
 405        "Line 1: Redundant bracket\n",
 406        "Found:\n",
 407        "(map head [ur, ul, dl, dr]) : [[10, 11, 12, 13, 14, 15, 16, 17]]\n",
 408        "Why not:\n",
 409        "map head [ur, ul, dl, dr] : [[10, 11, 12, 13, 14, 15, 16, 17]]"
 410       ]
 411      },
 412      "metadata": {},
 413      "output_type": "display_data"
 414     },
 415     {
 416      "data": {
 417       "text/plain": [
 418        "[1,1,1,1,10,11,12,13,14,15,16,17]"
 419       ]
 420      },
 421      "metadata": {},
 422      "output_type": "display_data"
 423     }
 424    ],
 425    "source": [
 426     "concat $  (map head [ur, ul, dl, dr]) : [[10, 11, 12, 13, 14, 15, 16, 17]]"
 427    ]
 428   },
 429   {
 430    "cell_type": "code",
 431    "execution_count": 21,
 432    "metadata": {},
 433    "outputs": [
 434     {
 435      "data": {
 436       "text/plain": [
 437        "[0,10,20,30,1,11,21,31,2,12,22,32]"
 438       ]
 439      },
 440      "metadata": {},
 441      "output_type": "display_data"
 442     }
 443    ],
 444    "source": [
 445     "interleave [[0,1,2], [10,11,12], [20, 21, 22], [30, 31, 32]]"
 446    ]
 447   },
 448   {
 449    "cell_type": "code",
 450    "execution_count": 22,
 451    "metadata": {},
 452    "outputs": [
 453     {
 454      "data": {
 455       "text/plain": [
 456        "[1,1,1,1,3,5,7,9,13,17,21,25,31,37,43,49,57,65,73,81]"
 457       ]
 458      },
 459      "metadata": {},
 460      "output_type": "display_data"
 461     }
 462    ],
 463    "source": [
 464     "take 20 $ interleave [ur, ul, dl, dr]"
 465    ]
 466   },
 467   {
 468    "cell_type": "code",
 469    "execution_count": 23,
 470    "metadata": {},
 471    "outputs": [
 472     {
 473      "data": {
 474       "text/html": [
 475        "<style>/* Styles used for the Hoogle display in the pager */\n",
 476        ".hoogle-doc {\n",
 477        "display: block;\n",
 478        "padding-bottom: 1.3em;\n",
 479        "padding-left: 0.4em;\n",
 480        "}\n",
 481        ".hoogle-code {\n",
 482        "display: block;\n",
 483        "font-family: monospace;\n",
 484        "white-space: pre;\n",
 485        "}\n",
 486        ".hoogle-text {\n",
 487        "display: block;\n",
 488        "}\n",
 489        ".hoogle-name {\n",
 490        "color: green;\n",
 491        "font-weight: bold;\n",
 492        "}\n",
 493        ".hoogle-head {\n",
 494        "font-weight: bold;\n",
 495        "}\n",
 496        ".hoogle-sub {\n",
 497        "display: block;\n",
 498        "margin-left: 0.4em;\n",
 499        "}\n",
 500        ".hoogle-package {\n",
 501        "font-weight: bold;\n",
 502        "font-style: italic;\n",
 503        "}\n",
 504        ".hoogle-module {\n",
 505        "font-weight: bold;\n",
 506        "}\n",
 507        ".hoogle-class {\n",
 508        "font-weight: bold;\n",
 509        "}\n",
 510        ".get-type {\n",
 511        "color: green;\n",
 512        "font-weight: bold;\n",
 513        "font-family: monospace;\n",
 514        "display: block;\n",
 515        "white-space: pre-wrap;\n",
 516        "}\n",
 517        ".show-type {\n",
 518        "color: green;\n",
 519        "font-weight: bold;\n",
 520        "font-family: monospace;\n",
 521        "margin-left: 1em;\n",
 522        "}\n",
 523        ".mono {\n",
 524        "font-family: monospace;\n",
 525        "display: block;\n",
 526        "}\n",
 527        ".err-msg {\n",
 528        "color: red;\n",
 529        "font-style: italic;\n",
 530        "font-family: monospace;\n",
 531        "white-space: pre;\n",
 532        "display: block;\n",
 533        "}\n",
 534        "#unshowable {\n",
 535        "color: red;\n",
 536        "font-weight: bold;\n",
 537        "}\n",
 538        ".err-msg.in.collapse {\n",
 539        "padding-top: 0.7em;\n",
 540        "}\n",
 541        ".highlight-code {\n",
 542        "white-space: pre;\n",
 543        "font-family: monospace;\n",
 544        "}\n",
 545        ".suggestion-warning { \n",
 546        "font-weight: bold;\n",
 547        "color: rgb(200, 130, 0);\n",
 548        "}\n",
 549        ".suggestion-error { \n",
 550        "font-weight: bold;\n",
 551        "color: red;\n",
 552        "}\n",
 553        ".suggestion-name {\n",
 554        "font-weight: bold;\n",
 555        "}\n",
 556        "</style><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 557        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[zip [0 ..] ur, (zip [0 ..] ul), (zip [0 ..] dl), (zip [0 ..] dr)]</div></div><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 558        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), zip [0 ..] ul, (zip [0 ..] dl), (zip [0 ..] dr)]</div></div><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 559        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), zip [0 ..] dl, (zip [0 ..] dr)]</div></div><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 560        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl), zip [0 ..] dr]</div></div>"
 561       ],
 562       "text/plain": [
 563        "Line 1: Redundant bracket\n",
 564        "Found:\n",
 565        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 566        " (zip [0 ..] dr)]\n",
 567        "Why not:\n",
 568        "[zip [0 ..] ur, (zip [0 ..] ul), (zip [0 ..] dl), (zip [0 ..] dr)]Line 1: Redundant bracket\n",
 569        "Found:\n",
 570        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 571        " (zip [0 ..] dr)]\n",
 572        "Why not:\n",
 573        "[(zip [0 ..] ur), zip [0 ..] ul, (zip [0 ..] dl), (zip [0 ..] dr)]Line 1: Redundant bracket\n",
 574        "Found:\n",
 575        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 576        " (zip [0 ..] dr)]\n",
 577        "Why not:\n",
 578        "[(zip [0 ..] ur), (zip [0 ..] ul), zip [0 ..] dl, (zip [0 ..] dr)]Line 1: Redundant bracket\n",
 579        "Found:\n",
 580        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 581        " (zip [0 ..] dr)]\n",
 582        "Why not:\n",
 583        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl), zip [0 ..] dr]"
 584       ]
 585      },
 586      "metadata": {},
 587      "output_type": "display_data"
 588     },
 589     {
 590      "data": {
 591       "text/plain": [
 592        "[(0,1),(1,3),(1,5),(1,7),(1,9),(2,13),(2,17),(2,21),(2,25),(3,31),(3,37),(3,43),(3,49),(4,57),(4,65),(4,73),(4,81),(5,91),(5,101),(5,111)]"
 593       ]
 594      },
 595      "metadata": {},
 596      "output_type": "display_data"
 597     }
 598    ],
 599    "source": [
 600     "take 20 $ drop 3 $ interleave [(zip [0..] ur), (zip [0..] ul), (zip [0..] dl), (zip [0..] dr)]"
 601    ]
 602   },
 603   {
 604    "cell_type": "code",
 605    "execution_count": 24,
 606    "metadata": {},
 607    "outputs": [],
 608    "source": [
 609     "target = 30"
 610    ]
 611   },
 612   {
 613    "cell_type": "code",
 614    "execution_count": 25,
 615    "metadata": {},
 616    "outputs": [
 617     {
 618      "data": {
 619       "text/html": [
 620        "<style>/* Styles used for the Hoogle display in the pager */\n",
 621        ".hoogle-doc {\n",
 622        "display: block;\n",
 623        "padding-bottom: 1.3em;\n",
 624        "padding-left: 0.4em;\n",
 625        "}\n",
 626        ".hoogle-code {\n",
 627        "display: block;\n",
 628        "font-family: monospace;\n",
 629        "white-space: pre;\n",
 630        "}\n",
 631        ".hoogle-text {\n",
 632        "display: block;\n",
 633        "}\n",
 634        ".hoogle-name {\n",
 635        "color: green;\n",
 636        "font-weight: bold;\n",
 637        "}\n",
 638        ".hoogle-head {\n",
 639        "font-weight: bold;\n",
 640        "}\n",
 641        ".hoogle-sub {\n",
 642        "display: block;\n",
 643        "margin-left: 0.4em;\n",
 644        "}\n",
 645        ".hoogle-package {\n",
 646        "font-weight: bold;\n",
 647        "font-style: italic;\n",
 648        "}\n",
 649        ".hoogle-module {\n",
 650        "font-weight: bold;\n",
 651        "}\n",
 652        ".hoogle-class {\n",
 653        "font-weight: bold;\n",
 654        "}\n",
 655        ".get-type {\n",
 656        "color: green;\n",
 657        "font-weight: bold;\n",
 658        "font-family: monospace;\n",
 659        "display: block;\n",
 660        "white-space: pre-wrap;\n",
 661        "}\n",
 662        ".show-type {\n",
 663        "color: green;\n",
 664        "font-weight: bold;\n",
 665        "font-family: monospace;\n",
 666        "margin-left: 1em;\n",
 667        "}\n",
 668        ".mono {\n",
 669        "font-family: monospace;\n",
 670        "display: block;\n",
 671        "}\n",
 672        ".err-msg {\n",
 673        "color: red;\n",
 674        "font-style: italic;\n",
 675        "font-family: monospace;\n",
 676        "white-space: pre;\n",
 677        "display: block;\n",
 678        "}\n",
 679        "#unshowable {\n",
 680        "color: red;\n",
 681        "font-weight: bold;\n",
 682        "}\n",
 683        ".err-msg.in.collapse {\n",
 684        "padding-top: 0.7em;\n",
 685        "}\n",
 686        ".highlight-code {\n",
 687        "white-space: pre;\n",
 688        "font-family: monospace;\n",
 689        "}\n",
 690        ".suggestion-warning { \n",
 691        "font-weight: bold;\n",
 692        "color: rgb(200, 130, 0);\n",
 693        "}\n",
 694        ".suggestion-error { \n",
 695        "font-weight: bold;\n",
 696        "color: red;\n",
 697        "}\n",
 698        ".suggestion-name {\n",
 699        "font-weight: bold;\n",
 700        "}\n",
 701        "</style><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 702        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[zip [0 ..] ur, (zip [0 ..] ul), (zip [0 ..] dl), (zip [0 ..] dr)]</div></div><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 703        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), zip [0 ..] ul, (zip [0 ..] dl), (zip [0 ..] dr)]</div></div><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 704        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), zip [0 ..] dl, (zip [0 ..] dr)]</div></div><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 705        " (zip [0 ..] dr)]</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl), zip [0 ..] dr]</div></div>"
 706       ],
 707       "text/plain": [
 708        "Line 1: Redundant bracket\n",
 709        "Found:\n",
 710        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 711        " (zip [0 ..] dr)]\n",
 712        "Why not:\n",
 713        "[zip [0 ..] ur, (zip [0 ..] ul), (zip [0 ..] dl), (zip [0 ..] dr)]Line 1: Redundant bracket\n",
 714        "Found:\n",
 715        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 716        " (zip [0 ..] dr)]\n",
 717        "Why not:\n",
 718        "[(zip [0 ..] ur), zip [0 ..] ul, (zip [0 ..] dl), (zip [0 ..] dr)]Line 1: Redundant bracket\n",
 719        "Found:\n",
 720        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 721        " (zip [0 ..] dr)]\n",
 722        "Why not:\n",
 723        "[(zip [0 ..] ur), (zip [0 ..] ul), zip [0 ..] dl, (zip [0 ..] dr)]Line 1: Redundant bracket\n",
 724        "Found:\n",
 725        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl),\n",
 726        " (zip [0 ..] dr)]\n",
 727        "Why not:\n",
 728        "[(zip [0 ..] ur), (zip [0 ..] ul), (zip [0 ..] dl), zip [0 ..] dr]"
 729       ]
 730      },
 731      "metadata": {},
 732      "output_type": "display_data"
 733     }
 734    ],
 735    "source": [
 736     "countedDiags = interleave [(zip [0..] ur), (zip [0..] ul), (zip [0..] dl), (zip [0..] dr)]"
 737    ]
 738   },
 739   {
 740    "cell_type": "code",
 741    "execution_count": 26,
 742    "metadata": {},
 743    "outputs": [
 744     {
 745      "data": {
 746       "text/html": [
 747        "<style>/* Styles used for the Hoogle display in the pager */\n",
 748        ".hoogle-doc {\n",
 749        "display: block;\n",
 750        "padding-bottom: 1.3em;\n",
 751        "padding-left: 0.4em;\n",
 752        "}\n",
 753        ".hoogle-code {\n",
 754        "display: block;\n",
 755        "font-family: monospace;\n",
 756        "white-space: pre;\n",
 757        "}\n",
 758        ".hoogle-text {\n",
 759        "display: block;\n",
 760        "}\n",
 761        ".hoogle-name {\n",
 762        "color: green;\n",
 763        "font-weight: bold;\n",
 764        "}\n",
 765        ".hoogle-head {\n",
 766        "font-weight: bold;\n",
 767        "}\n",
 768        ".hoogle-sub {\n",
 769        "display: block;\n",
 770        "margin-left: 0.4em;\n",
 771        "}\n",
 772        ".hoogle-package {\n",
 773        "font-weight: bold;\n",
 774        "font-style: italic;\n",
 775        "}\n",
 776        ".hoogle-module {\n",
 777        "font-weight: bold;\n",
 778        "}\n",
 779        ".hoogle-class {\n",
 780        "font-weight: bold;\n",
 781        "}\n",
 782        ".get-type {\n",
 783        "color: green;\n",
 784        "font-weight: bold;\n",
 785        "font-family: monospace;\n",
 786        "display: block;\n",
 787        "white-space: pre-wrap;\n",
 788        "}\n",
 789        ".show-type {\n",
 790        "color: green;\n",
 791        "font-weight: bold;\n",
 792        "font-family: monospace;\n",
 793        "margin-left: 1em;\n",
 794        "}\n",
 795        ".mono {\n",
 796        "font-family: monospace;\n",
 797        "display: block;\n",
 798        "}\n",
 799        ".err-msg {\n",
 800        "color: red;\n",
 801        "font-style: italic;\n",
 802        "font-family: monospace;\n",
 803        "white-space: pre;\n",
 804        "display: block;\n",
 805        "}\n",
 806        "#unshowable {\n",
 807        "color: red;\n",
 808        "font-weight: bold;\n",
 809        "}\n",
 810        ".err-msg.in.collapse {\n",
 811        "padding-top: 0.7em;\n",
 812        "}\n",
 813        ".highlight-code {\n",
 814        "white-space: pre;\n",
 815        "font-family: monospace;\n",
 816        "}\n",
 817        ".suggestion-warning { \n",
 818        "font-weight: bold;\n",
 819        "color: rgb(200, 130, 0);\n",
 820        "}\n",
 821        ".suggestion-error { \n",
 822        "font-weight: bold;\n",
 823        "color: red;\n",
 824        "}\n",
 825        ".suggestion-name {\n",
 826        "font-weight: bold;\n",
 827        "}\n",
 828        "</style><div class=\"suggestion-name\" style=\"clear:both;\">Use guards</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">result\n",
 829        "  = if pcd == ncd then\n",
 830        "      if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
 831        "        else ncd * 2 - (ncv - target)\n",
 832        "      else\n",
 833        "      if (target - pcv + 1) < ncv - target then\n",
 834        "        pcd * 2 - (target - pcv) + 2 else ncd * 2 - (ncv - target)</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">result\n",
 835        "  | pcd == ncd =\n",
 836        "    if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
 837        "      else ncd * 2 - (ncv - target)\n",
 838        "  | (target - pcv + 1) < ncv - target = pcd * 2 - (target - pcv) + 2\n",
 839        "  | otherwise = ncd * 2 - (ncv - target)</div></div><div class=\"suggestion-name\" style=\"clear:both;\">Redundant bracket</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">(result, pcd, ncd, (target - pcv + 2), ncv - target)</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">(result, pcd, ncd, target - pcv + 2, ncv - target)</div></div>"
 840       ],
 841       "text/plain": [
 842        "Line 4: Use guards\n",
 843        "Found:\n",
 844        "result\n",
 845        "  = if pcd == ncd then\n",
 846        "      if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
 847        "        else ncd * 2 - (ncv - target)\n",
 848        "      else\n",
 849        "      if (target - pcv + 1) < ncv - target then\n",
 850        "        pcd * 2 - (target - pcv) + 2 else ncd * 2 - (ncv - target)\n",
 851        "Why not:\n",
 852        "result\n",
 853        "  | pcd == ncd =\n",
 854        "    if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
 855        "      else ncd * 2 - (ncv - target)\n",
 856        "  | (target - pcv + 1) < ncv - target = pcd * 2 - (target - pcv) + 2\n",
 857        "  | otherwise = ncd * 2 - (ncv - target)Line 12: Redundant bracket\n",
 858        "Found:\n",
 859        "(result, pcd, ncd, (target - pcv + 2), ncv - target)\n",
 860        "Why not:\n",
 861        "(result, pcd, ncd, target - pcv + 2, ncv - target)"
 862       ]
 863      },
 864      "metadata": {},
 865      "output_type": "display_data"
 866     },
 867     {
 868      "data": {
 869       "text/plain": [
 870        "(7,4,4,3,7)"
 871       ]
 872      },
 873      "metadata": {},
 874      "output_type": "display_data"
 875     }
 876    ],
 877    "source": [
 878     "target = 58\n",
 879     "let corners =  head $ dropWhile ((< target) . snd . head . tail) $ tails countedDiags\n",
 880     "    (pcd, pcv) = head corners\n",
 881     "    (ncd, ncv) = head $ tail corners\n",
 882     "    result = if pcd == ncd \n",
 883     "                then if (target - pcv + 2) < ncv - target\n",
 884     "                     then pcd * 2 - (target - pcv)\n",
 885     "                     else ncd * 2 - (ncv - target)\n",
 886     "             else if (target - pcv + 1) < ncv - target\n",
 887     "                     then pcd * 2 - (target - pcv) + 2\n",
 888     "                     else ncd * 2 - (ncv - target)\n",
 889     "            \n",
 890     "    in (result, pcd, ncd, (target - pcv + 2), ncv - target)"
 891    ]
 892   },
 893   {
 894    "cell_type": "code",
 895    "execution_count": 27,
 896    "metadata": {},
 897    "outputs": [
 898     {
 899      "data": {
 900       "text/html": [
 901        "<style>/* Styles used for the Hoogle display in the pager */\n",
 902        ".hoogle-doc {\n",
 903        "display: block;\n",
 904        "padding-bottom: 1.3em;\n",
 905        "padding-left: 0.4em;\n",
 906        "}\n",
 907        ".hoogle-code {\n",
 908        "display: block;\n",
 909        "font-family: monospace;\n",
 910        "white-space: pre;\n",
 911        "}\n",
 912        ".hoogle-text {\n",
 913        "display: block;\n",
 914        "}\n",
 915        ".hoogle-name {\n",
 916        "color: green;\n",
 917        "font-weight: bold;\n",
 918        "}\n",
 919        ".hoogle-head {\n",
 920        "font-weight: bold;\n",
 921        "}\n",
 922        ".hoogle-sub {\n",
 923        "display: block;\n",
 924        "margin-left: 0.4em;\n",
 925        "}\n",
 926        ".hoogle-package {\n",
 927        "font-weight: bold;\n",
 928        "font-style: italic;\n",
 929        "}\n",
 930        ".hoogle-module {\n",
 931        "font-weight: bold;\n",
 932        "}\n",
 933        ".hoogle-class {\n",
 934        "font-weight: bold;\n",
 935        "}\n",
 936        ".get-type {\n",
 937        "color: green;\n",
 938        "font-weight: bold;\n",
 939        "font-family: monospace;\n",
 940        "display: block;\n",
 941        "white-space: pre-wrap;\n",
 942        "}\n",
 943        ".show-type {\n",
 944        "color: green;\n",
 945        "font-weight: bold;\n",
 946        "font-family: monospace;\n",
 947        "margin-left: 1em;\n",
 948        "}\n",
 949        ".mono {\n",
 950        "font-family: monospace;\n",
 951        "display: block;\n",
 952        "}\n",
 953        ".err-msg {\n",
 954        "color: red;\n",
 955        "font-style: italic;\n",
 956        "font-family: monospace;\n",
 957        "white-space: pre;\n",
 958        "display: block;\n",
 959        "}\n",
 960        "#unshowable {\n",
 961        "color: red;\n",
 962        "font-weight: bold;\n",
 963        "}\n",
 964        ".err-msg.in.collapse {\n",
 965        "padding-top: 0.7em;\n",
 966        "}\n",
 967        ".highlight-code {\n",
 968        "white-space: pre;\n",
 969        "font-family: monospace;\n",
 970        "}\n",
 971        ".suggestion-warning { \n",
 972        "font-weight: bold;\n",
 973        "color: rgb(200, 130, 0);\n",
 974        "}\n",
 975        ".suggestion-error { \n",
 976        "font-weight: bold;\n",
 977        "color: red;\n",
 978        "}\n",
 979        ".suggestion-name {\n",
 980        "font-weight: bold;\n",
 981        "}\n",
 982        "</style><div class=\"suggestion-name\" style=\"clear:both;\">Use guards</div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Found:</div><div class=\"highlight-code\" id=\"haskell\">result\n",
 983        "  = if pcd == ncd then\n",
 984        "      if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
 985        "        else ncd * 2 - (ncv - target)\n",
 986        "      else\n",
 987        "      if (target - pcv + 1) < ncv - target then\n",
 988        "        pcd * 2 - (target - pcv) + 2 else ncd * 2 - (ncv - target)</div></div><div class=\"suggestion-row\" style=\"float: left;\"><div class=\"suggestion-warning\">Why Not:</div><div class=\"highlight-code\" id=\"haskell\">result\n",
 989        "  | pcd == ncd =\n",
 990        "    if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
 991        "      else ncd * 2 - (ncv - target)\n",
 992        "  | (target - pcv + 1) < ncv - target = pcd * 2 - (target - pcv) + 2\n",
 993        "  | otherwise = ncd * 2 - (ncv - target)</div></div>"
 994       ],
 995       "text/plain": [
 996        "Line 4: Use guards\n",
 997        "Found:\n",
 998        "result\n",
 999        "  = if pcd == ncd then\n",
1000        "      if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
1001        "        else ncd * 2 - (ncv - target)\n",
1002        "      else\n",
1003        "      if (target - pcv + 1) < ncv - target then\n",
1004        "        pcd * 2 - (target - pcv) + 2 else ncd * 2 - (ncv - target)\n",
1005        "Why not:\n",
1006        "result\n",
1007        "  | pcd == ncd =\n",
1008        "    if (target - pcv + 2) < ncv - target then pcd * 2 - (target - pcv)\n",
1009        "      else ncd * 2 - (ncv - target)\n",
1010        "  | (target - pcv + 1) < ncv - target = pcd * 2 - (target - pcv) + 2\n",
1011        "  | otherwise = ncd * 2 - (ncv - target)"
1012       ]
1013      },
1014      "metadata": {},
1015      "output_type": "display_data"
1016     },
1017     {
1018      "data": {
1019       "text/plain": [
1020        "480"
1021       ]
1022      },
1023      "metadata": {},
1024      "output_type": "display_data"
1025     }
1026    ],
1027    "source": [
1028     "target = 347991\n",
1029     "let corners =  head $ dropWhile ((< target) . snd . head . tail) $ tails countedDiags\n",
1030     "    (pcd, pcv) = head corners\n",
1031     "    (ncd, ncv) = head $ tail corners\n",
1032     "    result = if pcd == ncd \n",
1033     "                then if (target - pcv + 2) < ncv - target\n",
1034     "                     then pcd * 2 - (target - pcv)\n",
1035     "                     else ncd * 2 - (ncv - target)\n",
1036     "             else if (target - pcv + 1) < ncv - target\n",
1037     "                     then pcd * 2 - (target - pcv) + 2\n",
1038     "                     else ncd * 2 - (ncv - target)\n",
1039     "            \n",
1040     "    in result"
1041    ]
1042   },
1043   {
1044    "cell_type": "code",
1045    "execution_count": 28,
1046    "metadata": {},
1047    "outputs": [],
1048    "source": [
1049     "plainDiags = map snd countedDiags"
1050    ]
1051   },
1052   {
1053    "cell_type": "code",
1054    "execution_count": 29,
1055    "metadata": {},
1056    "outputs": [
1057     {
1058      "data": {
1059       "text/plain": [
1060        "[1,3,5,7,9,13,17,21,25,31,37,43,49,57,65,73,81,91,101,111]"
1061       ]
1062      },
1063      "metadata": {},
1064      "output_type": "display_data"
1065     }
1066    ],
1067    "source": [
1068     "take 20 $ drop 3 plainDiags"
1069    ]
1070   },
1071   {
1072    "cell_type": "code",
1073    "execution_count": 30,
1074    "metadata": {},
1075    "outputs": [
1076     {
1077      "data": {
1078       "text/plain": [
1079        "[1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10]"
1080       ]
1081      },
1082      "metadata": {},
1083      "output_type": "display_data"
1084     }
1085    ],
1086    "source": [
1087     "steps =  concat $ zipWith (\\a b -> [a,b]) [1..] [1..]\n",
1088     "take 20 steps"
1089    ]
1090   },
1091   {
1092    "cell_type": "code",
1093    "execution_count": 31,
1094    "metadata": {},
1095    "outputs": [],
1096    "source": [
1097     "up    (a, b) = (a, b + 1)\n",
1098     "down  (a, b) = (a, b - 1)\n",
1099     "left  (a, b) = (a - 1, b)\n",
1100     "right (a, b) = (a + 1, b)\n",
1101     "directions = [right, up, left, down]"
1102    ]
1103   },
1104   {
1105    "cell_type": "code",
1106    "execution_count": 32,
1107    "metadata": {},
1108    "outputs": [
1109     {
1110      "data": {
1111       "text/html": [
1112        "<style>/* Styles used for the Hoogle display in the pager */\n",
1113        ".hoogle-doc {\n",
1114        "display: block;\n",
1115        "padding-bottom: 1.3em;\n",
1116        "padding-left: 0.4em;\n",
1117        "}\n",
1118        ".hoogle-code {\n",
1119        "display: block;\n",
1120        "font-family: monospace;\n",
1121        "white-space: pre;\n",
1122        "}\n",
1123        ".hoogle-text {\n",
1124        "display: block;\n",
1125        "}\n",
1126        ".hoogle-name {\n",
1127        "color: green;\n",
1128        "font-weight: bold;\n",
1129        "}\n",
1130        ".hoogle-head {\n",
1131        "font-weight: bold;\n",
1132        "}\n",
1133        ".hoogle-sub {\n",
1134        "display: block;\n",
1135        "margin-left: 0.4em;\n",
1136        "}\n",
1137        ".hoogle-package {\n",
1138        "font-weight: bold;\n",
1139        "font-style: italic;\n",
1140        "}\n",
1141        ".hoogle-module {\n",
1142        "font-weight: bold;\n",
1143        "}\n",
1144        ".hoogle-class {\n",
1145        "font-weight: bold;\n",
1146        "}\n",
1147        ".get-type {\n",
1148        "color: green;\n",
1149        "font-weight: bold;\n",
1150        "font-family: monospace;\n",
1151        "display: block;\n",
1152        "white-space: pre-wrap;\n",
1153        "}\n",
1154        ".show-type {\n",
1155        "color: green;\n",
1156        "font-weight: bold;\n",
1157        "font-family: monospace;\n",
1158        "margin-left: 1em;\n",
1159        "}\n",
1160        ".mono {\n",
1161        "font-family: monospace;\n",
1162        "display: block;\n",
1163        "}\n",
1164        ".err-msg {\n",
1165        "color: red;\n",
1166        "font-style: italic;\n",
1167        "font-family: monospace;\n",
1168        "white-space: pre;\n",
1169        "display: block;\n",
1170        "}\n",
1171        "#unshowable {\n",
1172        "color: red;\n",
1173        "font-weight: bold;\n",
1174        "}\n",
1175        ".err-msg.in.collapse {\n",
1176        "padding-top: 0.7em;\n",
1177        "}\n",
1178        ".highlight-code {\n",
1179        "white-space: pre;\n",
1180        "font-family: monospace;\n",
1181        "}\n",
1182        ".suggestion-warning { \n",
1183        "font-weight: bold;\n",
1184        "color: rgb(200, 130, 0);\n",
1185        "}\n",
1186        ".suggestion-error { \n",
1187        "font-weight: bold;\n",
1188        "color: red;\n",
1189        "}\n",
1190        ".suggestion-name {\n",
1191        "font-weight: bold;\n",
1192        "}\n",
1193        "</style><span class='err-msg'>&lt;interactive&gt;:1:1: error:<br/>    • No instance for (Show ((t10, t0) -&gt; (t10, t0))) arising from a use of ‘print’<br/>        (maybe you haven't applied a function to enough arguments?)<br/>    • In a stmt of an interactive GHCi command: print it</span>"
1194       ],
1195       "text/plain": [
1196        "<interactive>:1:1: error:\n",
1197        "    • No instance for (Show ((t10, t0) -> (t10, t0))) arising from a use of ‘print’\n",
1198        "        (maybe you haven't applied a function to enough arguments?)\n",
1199        "    • In a stmt of an interactive GHCi command: print it"
1200       ]
1201      },
1202      "metadata": {},
1203      "output_type": "display_data"
1204     }
1205    ],
1206    "source": [
1207     "take 20 $ concat $ zipWith replicate steps (cycle directions)"
1208    ]
1209   },
1210   {
1211    "cell_type": "code",
1212    "execution_count": 33,
1213    "metadata": {},
1214    "outputs": [
1215     {
1216      "data": {
1217       "text/plain": [
1218        "[1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10]"
1219       ]
1220      },
1221      "metadata": {},
1222      "output_type": "display_data"
1223     }
1224    ],
1225    "source": [
1226     "take 20 steps"
1227    ]
1228   },
1229   {
1230    "cell_type": "code",
1231    "execution_count": 34,
1232    "metadata": {},
1233    "outputs": [],
1234    "source": [
1235     "locations = scanl (\\c f -> f c) (0,0) $ concat $ zipWith replicate steps (cycle directions)\n",
1236     "    where\n",
1237     "        steps = concat $ zipWith (\\a b -> [a,b]) [1..] [1..]"
1238    ]
1239   },
1240   {
1241    "cell_type": "code",
1242    "execution_count": 35,
1243    "metadata": {},
1244    "outputs": [
1245     {
1246      "data": {
1247       "text/plain": [
1248        "[(0,0),(1,0),(1,1),(0,1),(-1,1),(-1,0),(-1,-1),(0,-1),(1,-1),(2,-1),(2,0),(2,1),(2,2),(1,2),(0,2),(-1,2),(-2,2),(-2,1),(-2,0),(-2,-1)]"
1249       ]
1250      },
1251      "metadata": {},
1252      "output_type": "display_data"
1253     }
1254    ],
1255    "source": [
1256     "take 20 locations"
1257    ]
1258   },
1259   {
1260    "cell_type": "code",
1261    "execution_count": 36,
1262    "metadata": {},
1263    "outputs": [
1264     {
1265      "data": {
1266       "text/plain": [
1267        "fromList [((0,0),1)]"
1268       ]
1269      },
1270      "metadata": {},
1271      "output_type": "display_data"
1272     }
1273    ],
1274    "source": [
1275     "M.singleton (0, 0) 1"
1276    ]
1277   },
1278   {
1279    "cell_type": "code",
1280    "execution_count": 37,
1281    "metadata": {},
1282    "outputs": [
1283     {
1284      "data": {
1285       "text/plain": [
1286        "fromList [((0,0),1),((0,1),4),((1,1),2),((1,0),1),((-1,1),5),((-1,0),10)]"
1287       ]
1288      },
1289      "metadata": {},
1290      "output_type": "display_data"
1291     }
1292    ],
1293    "source": [
1294     "m0 = M.fromList [((0,0), 1),((1,0), 1), ((1,1), 2), ((0,1), 4), ((-1,1), 5), ((-1,0), 10)]\n",
1295     "m0"
1296    ]
1297   },
1298   {
1299    "cell_type": "code",
1300    "execution_count": 38,
1301    "metadata": {},
1302    "outputs": [],
1303    "source": [
1304     "adjacentMap (r, c) = M.filterWithKey adjacent \n",
1305     "    where adjacent k _ = abs (fst k - r) <= 1 && abs (snd k - c) <= 1"
1306    ]
1307   },
1308   {
1309    "cell_type": "code",
1310    "execution_count": 39,
1311    "metadata": {},
1312    "outputs": [
1313     {
1314      "data": {
1315       "text/plain": [
1316        "fromList [((0,0),1),((0,1),4),((-1,1),5),((-1,0),10)]"
1317       ]
1318      },
1319      "metadata": {},
1320      "output_type": "display_data"
1321     }
1322    ],
1323    "source": [
1324     "adjacentMap (-1, 1) m0"
1325    ]
1326   },
1327   {
1328    "cell_type": "code",
1329    "execution_count": 40,
1330    "metadata": {},
1331    "outputs": [],
1332    "source": [
1333     "adjacentMapSum here = M.foldr (+) 0 . adjacentMap here"
1334    ]
1335   },
1336   {
1337    "cell_type": "code",
1338    "execution_count": 41,
1339    "metadata": {},
1340    "outputs": [
1341     {
1342      "data": {
1343       "text/plain": [
1344        "20"
1345       ]
1346      },
1347      "metadata": {},
1348      "output_type": "display_data"
1349     }
1350    ],
1351    "source": [
1352     "adjacentMapSum (-1, 1) m0"
1353    ]
1354   },
1355   {
1356    "cell_type": "code",
1357    "execution_count": 42,
1358    "metadata": {},
1359    "outputs": [],
1360    "source": [
1361     "type Location = (Int, Int)\n",
1362     "type Memory = M.HashMap Location Int"
1363    ]
1364   },
1365   {
1366    "cell_type": "code",
1367    "execution_count": 43,
1368    "metadata": {},
1369    "outputs": [],
1370    "source": [
1371     "emptyMemory = M.singleton (0, 0) 1    "
1372    ]
1373   },
1374   {
1375    "cell_type": "code",
1376    "execution_count": 44,
1377    "metadata": {},
1378    "outputs": [],
1379    "source": [
1380     "updateMemoryOnce :: Location -> State Memory Int\n",
1381     "updateMemoryOnce here = \n",
1382     "    do m0 <- get\n",
1383     "       let total = adjacentMapSum here m0\n",
1384     "       put (M.insert here total m0)\n",
1385     "       return total"
1386    ]
1387   },
1388   {
1389    "cell_type": "code",
1390    "execution_count": 45,
1391    "metadata": {},
1392    "outputs": [],
1393    "source": [
1394     "updateMemory :: [Location] -> State Memory Int\n",
1395     "updateMemory [] = do return 0\n",
1396     "updateMemory (l:ls) = \n",
1397     "    do  updateMemoryOnce l\n",
1398     "        updateMemory ls"
1399    ]
1400   },
1401   {
1402    "cell_type": "code",
1403    "execution_count": 46,
1404    "metadata": {},
1405    "outputs": [
1406     {
1407      "data": {
1408       "text/plain": [
1409        "(0,fromList [((0,0),1),((5,-1),6573553),((1,3),5336),((-1,-3),37402),((-4,4),369601),((4,-4),2909666),((0,1),4),((5,-2),6262851),((1,2),122),((-1,-4),2292124),((4,-3),48065),((-4,5),24242690),((0,2),133),((2,4),279138),((5,-3),6013560),((-3,5),23510079),((1,1),2),((-1,-1),11),((4,-2),98098),((0,3),5733),((2,5),18565223),((5,-4),2957731),((-3,4),363010),((1,0),1),((-1,-2),747),((4,-1),103128),((0,4),312453),((2,2),59),((-2,-2),362),((-5,5),24612291),((-3,3),6591),((3,-3),47108),((-4,0),875851),((0,5),20390510),((-2,-1),351),((2,3),5022),((-3,2),13486),((3,-4),2814493),((-4,1),830037),((2,0),54),((-2,-4),2179400),((3,-1),1968),((-3,1),14267),((1,5),19452043),((-4,2),787032),((2,1),57),((-2,-3),35487),((3,-2),957),((-3,0),15252),((1,4),295229),((-4,3),752688),((4,4),130654),((-4,-4),1026827),((-1,5),21383723),((3,1),2275),((-3,-1),16295),((-2,2),147),((2,-2),931),((-4,-3),1009457),((4,5),17048404),((-1,4),330785),((3,0),2105),((-3,-2),17008),((2,-1),26),((-2,3),6444),((-4,-2),975079),((3,3),2450),((-3,-3),17370),((5,5),8391037),((-2,0),330),((2,-4),2674100),((-4,-1),924406),((3,2),2391),((-3,-4),2089141),((5,4),8260383),((-2,1),304),((2,-3),45220),((4,0),109476),((-1,1),5),((1,-1),25),((3,5),17724526),((5,3),8001525),((0,-4),2411813),((4,1),116247),((-1,0),10),((1,-2),880),((3,4),266330),((5,2),7619304),((0,-3),39835),((4,2),123363),((-1,3),6155),((1,-3),42452),((5,1),7251490),((-2,4),349975),((0,-2),806),((4,3),128204),((-1,2),142),((1,-4),2539320),((5,0),6902404),((-2,5),22427493),((0,-1),23)])"
1410       ]
1411      },
1412      "metadata": {},
1413      "output_type": "display_data"
1414     }
1415    ],
1416    "source": [
1417     "runState (updateMemory (take 100 $ drop 1 locations)) emptyMemory"
1418    ]
1419   },
1420   {
1421    "cell_type": "code",
1422    "execution_count": 51,
1423    "metadata": {},
1424    "outputs": [],
1425    "source": [
1426     "memoryValues = execState (updateMemory (take 100 $ drop 1 locations)) emptyMemory"
1427    ]
1428   },
1429   {
1430    "cell_type": "code",
1431    "execution_count": 48,
1432    "metadata": {},
1433    "outputs": [
1434     {
1435      "data": {
1436       "text/plain": [
1437        "347991"
1438       ]
1439      },
1440      "metadata": {},
1441      "output_type": "display_data"
1442     }
1443    ],
1444    "source": [
1445     "target"
1446    ]
1447   },
1448   {
1449    "cell_type": "code",
1450    "execution_count": 52,
1451    "metadata": {},
1452    "outputs": [
1453     {
1454      "data": {
1455       "text/plain": [
1456        "(-2,4)"
1457       ]
1458      },
1459      "metadata": {},
1460      "output_type": "display_data"
1461     }
1462    ],
1463    "source": [
1464     "head $ dropWhile (\\l -> memoryValues!l <= target) locations"
1465    ]
1466   },
1467   {
1468    "cell_type": "code",
1469    "execution_count": 53,
1470    "metadata": {},
1471    "outputs": [
1472     {
1473      "data": {
1474       "text/plain": [
1475        "349975"
1476       ]
1477      },
1478      "metadata": {},
1479      "output_type": "display_data"
1480     }
1481    ],
1482    "source": [
1483     "(!) memoryValues $ head $ dropWhile (\\l -> memoryValues!l <= target) locations"
1484    ]
1485   },
1486   {
1487    "cell_type": "code",
1488    "execution_count": null,
1489    "metadata": {},
1490    "outputs": [],
1491    "source": []
1492   }
1493  ],
1494  "metadata": {
1495   "kernelspec": {
1496    "display_name": "Haskell",
1497    "language": "haskell",
1498    "name": "haskell"
1499   },
1500   "language_info": {
1501    "codemirror_mode": "ihaskell",
1502    "file_extension": ".hs",
1503    "name": "haskell",
1504    "version": "8.0.2"
1505   }
1506  },
1507  "nbformat": 4,
1508  "nbformat_minor": 2
1509 }