euler42.ipynb

   1 {
   2  "cells": [
   3   {
   4    "cell_type": "code",
   5    "execution_count": 1,
   6    "metadata": {
   7     "collapsed": false
   8    },
   9    "outputs": [
  10     {
  11      "data": {
  12       "text/plain": [
  13        "[\"A\", \"ABILITY\", \"ABLE\", \"ABOUT\", \"ABOVE\", \"ABSENCE\", \"ABSOLUTELY\", \"ACADEMIC\", \"ACCEPT\", \"ACCESS\", \"ACCIDENT\"]"
  14       ]
  15      },
  16      "execution_count": 1,
  17      "metadata": {},
  18      "output_type": "execute_result"
  19     }
  20    ],
  21    "source": [
  22     "words = File.read(\"p042_words.txt\").split(\",\").map {|w| w[1..-2]}\n",
  23     "words[0..10]"
  24    ]
  25   },
  26   {
  27    "cell_type": "code",
  28    "execution_count": 2,
  29    "metadata": {
  30     "collapsed": false
  31    },
  32    "outputs": [
  33     {
  34      "data": {
  35       "text/plain": [
  36        ":grow"
  37       ]
  38      },
  39      "execution_count": 2,
  40      "metadata": {},
  41      "output_type": "execute_result"
  42     }
  43    ],
  44    "source": [
  45     "require 'singleton'\n",
  46     "\n",
  47     "class TriangleN\n",
  48     "  include Enumerable\n",
  49     "  include Singleton\n",
  50     "\n",
  51     "  def initialize\n",
  52     "    @tns = [1]\n",
  53     "  end\n",
  54     "  \n",
  55     "  def is_triangle?(n)\n",
  56     "    self.grow(n)\n",
  57     "    @tns.include?(n)\n",
  58     "  end\n",
  59     "  \n",
  60     "  def grow(n)\n",
  61     "    while n > @tns[-1]\n",
  62     "      @tns += [(@tns.length+1) * (@tns.length+2) / 2]\n",
  63     "    end\n",
  64     "  end\n",
  65     "end"
  66    ]
  67   },
  68   {
  69    "cell_type": "code",
  70    "execution_count": 3,
  71    "metadata": {
  72     "collapsed": false
  73    },
  74    "outputs": [
  75     {
  76      "data": {
  77       "text/plain": [
  78        "#<TriangleN:0x00563e39321180 @tns=[1]>"
  79       ]
  80      },
  81      "execution_count": 3,
  82      "metadata": {},
  83      "output_type": "execute_result"
  84     }
  85    ],
  86    "source": [
  87     "trins = TriangleN.instance"
  88    ]
  89   },
  90   {
  91    "cell_type": "code",
  92    "execution_count": 4,
  93    "metadata": {
  94     "collapsed": false
  95    },
  96    "outputs": [
  97     {
  98      "data": {
  99       "text/plain": [
 100        "true"
 101       ]
 102      },
 103      "execution_count": 4,
 104      "metadata": {},
 105      "output_type": "execute_result"
 106     }
 107    ],
 108    "source": [
 109     "trins.is_triangle? 10"
 110    ]
 111   },
 112   {
 113    "cell_type": "code",
 114    "execution_count": 5,
 115    "metadata": {
 116     "collapsed": false
 117    },
 118    "outputs": [
 119     {
 120      "data": {
 121       "text/plain": [
 122        "false"
 123       ]
 124      },
 125      "execution_count": 5,
 126      "metadata": {},
 127      "output_type": "execute_result"
 128     }
 129    ],
 130    "source": [
 131     "trins.is_triangle? 11"
 132    ]
 133   },
 134   {
 135    "cell_type": "code",
 136    "execution_count": 6,
 137    "metadata": {
 138     "collapsed": false
 139    },
 140    "outputs": [
 141     {
 142      "data": {
 143       "text/plain": [
 144        ":triangle_sum?"
 145       ]
 146      },
 147      "execution_count": 6,
 148      "metadata": {},
 149      "output_type": "execute_result"
 150     }
 151    ],
 152    "source": [
 153     "class String\n",
 154     "  \n",
 155     "  @@triangles = TriangleN.instance\n",
 156     "  \n",
 157     "  def to_nums\n",
 158     "    self.chars.map {|c| c.ord - 'A'.ord + 1}\n",
 159     "  end\n",
 160     "  \n",
 161     "  def num_sum\n",
 162     "    self.to_nums.sum\n",
 163     "  end\n",
 164     "  \n",
 165     "  def triangle_sum?\n",
 166     "    @@triangles.is_triangle?(self.num_sum)\n",
 167     "  end\n",
 168     "end"
 169    ]
 170   },
 171   {
 172    "cell_type": "code",
 173    "execution_count": 7,
 174    "metadata": {
 175     "collapsed": false
 176    },
 177    "outputs": [
 178     {
 179      "data": {
 180       "text/plain": [
 181        "[19, 11, 25]"
 182       ]
 183      },
 184      "execution_count": 7,
 185      "metadata": {},
 186      "output_type": "execute_result"
 187     }
 188    ],
 189    "source": [
 190     "\"SKY\".to_nums"
 191    ]
 192   },
 193   {
 194    "cell_type": "code",
 195    "execution_count": 8,
 196    "metadata": {
 197     "collapsed": false
 198    },
 199    "outputs": [
 200     {
 201      "data": {
 202       "text/plain": [
 203        "55"
 204       ]
 205      },
 206      "execution_count": 8,
 207      "metadata": {},
 208      "output_type": "execute_result"
 209     }
 210    ],
 211    "source": [
 212     "\"SKY\".num_sum"
 213    ]
 214   },
 215   {
 216    "cell_type": "code",
 217    "execution_count": 9,
 218    "metadata": {
 219     "collapsed": false
 220    },
 221    "outputs": [
 222     {
 223      "data": {
 224       "text/plain": [
 225        "true"
 226       ]
 227      },
 228      "execution_count": 9,
 229      "metadata": {},
 230      "output_type": "execute_result"
 231     }
 232    ],
 233    "source": [
 234     "trins.is_triangle? \"SKY\".num_sum"
 235    ]
 236   },
 237   {
 238    "cell_type": "code",
 239    "execution_count": 10,
 240    "metadata": {
 241     "collapsed": false
 242    },
 243    "outputs": [
 244     {
 245      "data": {
 246       "text/plain": [
 247        "true"
 248       ]
 249      },
 250      "execution_count": 10,
 251      "metadata": {},
 252      "output_type": "execute_result"
 253     }
 254    ],
 255    "source": [
 256     "\"SKY\".triangle_sum?"
 257    ]
 258   },
 259   {
 260    "cell_type": "code",
 261    "execution_count": 11,
 262    "metadata": {
 263     "collapsed": false
 264    },
 265    "outputs": [
 266     {
 267      "data": {
 268       "text/plain": [
 269        "162"
 270       ]
 271      },
 272      "execution_count": 11,
 273      "metadata": {},
 274      "output_type": "execute_result"
 275     }
 276    ],
 277    "source": [
 278     "words.select {|w| w.triangle_sum?}.length"
 279    ]
 280   },
 281   {
 282    "cell_type": "code",
 283    "execution_count": 12,
 284    "metadata": {
 285     "collapsed": false
 286    },
 287    "outputs": [
 288     {
 289      "data": {
 290       "text/plain": [
 291        "[\"A\", \"ABILITY\", \"ABOVE\", \"ACCOMPANY\", \"ACHIEVEMENT\", \"AGENCY\", \"AGREE\", \"AIR\", \"ALREADY\", \"AN\", \"ANCIENT\", \"APPARENT\", \"APPOINT\", \"APPROACH\", \"ASSUME\", \"AT\", \"ATMOSPHERE\", \"BAG\", \"BAND\", \"BANK\", \"BAR\", \"BEAT\", \"BELONG\", \"BENEATH\", \"BONE\", \"BOTH\", \"BRIDGE\", \"BUILDING\", \"BURN\", \"CALL\", \"CAPACITY\", \"CAREFUL\", \"CASE\", \"CHILD\", \"CIVIL\", \"CLOSELY\", \"COME\", \"CONFIDENCE\", \"CONFIRM\", \"CONSERVATIVE\", \"CONSTRUCTION\", \"CONTENT\", \"COULD\", \"CURRENTLY\", \"DECISION\", \"DEFINITION\", \"DEMOCRATIC\", \"DEPUTY\", \"DESPITE\", \"DISTINCTION\", \"EAST\", \"EDGE\", \"EDUCATIONAL\", \"EFFECT\", \"EQUIPMENT\", \"EVENT\", \"FACE\", \"FAIL\", \"FAMILY\", \"FEEL\", \"FIELD\", \"FIGURE\", \"FLOOR\", \"FREEDOM\", \"FUND\", \"FUTURE\", \"GENTLEMAN\", \"GREY\", \"GROWTH\", \"HAIR\", \"HAPPY\", \"HAVE\", \"HERE\", \"HIS\", \"IF\", \"INCIDENT\", \"INCREASED\", \"INCREASINGLY\", \"INDIVIDUAL\", \"INSTRUMENT\", \"INTEND\", \"INTENTION\", \"IS\", \"LAW\", \"LEADER\", \"LEAVE\", \"LENGTH\", \"LESS\", \"LITTLE\", \"LOVELY\", \"MAN\", \"MATCH\", \"MERELY\", \"MILK\", \"MISTAKE\", \"MOVE\", \"MUCH\", \"NEED\", \"NOTICE\", \"OBJECT\", \"OBJECTIVE\", \"OF\", \"OIL\", \"ONLY\", \"OTHER\", \"OURSELVES\", \"PART\", \"PASS\", \"PATH\", \"PERFORM\", \"PRISON\", \"PRIVATE\", \"PROBABLY\", \"PROCEDURE\", \"QUALITY\", \"QUESTION\", \"RANGE\", \"READ\", \"REAL\", \"RELIEF\", \"REMOVE\", \"REPRESENT\", \"REQUEST\", \"RESPOND\", \"RIDE\", \"SAMPLE\", \"SAY\", \"SEAT\", \"SECURITY\", \"SINGLE\", \"SKY\", \"SOIL\", \"SOLICITOR\", \"SONG\", \"SOUTHERN\", \"SPIRIT\", \"START\", \"SUGGESTION\", \"TALL\", \"TAX\", \"THEORY\", \"THREATEN\", \"THROUGHOUT\", \"TITLE\", \"TOOTH\", \"TOTALLY\", \"TRAVEL\", \"TYPE\", \"UNABLE\", \"UNDERSTAND\", \"UPON\", \"USE\", \"VARIOUS\", \"VARY\", \"VIDEO\", \"WAGE\", \"WARM\", \"WATCH\", \"WE\", \"WHILST\", \"WIDELY\", \"WOMAN\"]"
 292       ]
 293      },
 294      "execution_count": 12,
 295      "metadata": {},
 296      "output_type": "execute_result"
 297     }
 298    ],
 299    "source": [
 300     "words.select {|w| w.triangle_sum?}"
 301    ]
 302   },
 303   {
 304    "cell_type": "code",
 305    "execution_count": 13,
 306    "metadata": {
 307     "collapsed": false
 308    },
 309    "outputs": [
 310     {
 311      "data": {
 312       "text/plain": [
 313        "\"#<TriangleN:0x00563e39321180 @tns=[1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 105, 120, 136, 153, 171, 190, 210]>\""
 314       ]
 315      },
 316      "execution_count": 13,
 317      "metadata": {},
 318      "output_type": "execute_result"
 319     }
 320    ],
 321    "source": [
 322     "trins.inspect"
 323    ]
 324   },
 325   {
 326    "cell_type": "code",
 327    "execution_count": null,
 328    "metadata": {
 329     "collapsed": true
 330    },
 331    "outputs": [],
 332    "source": []
 333   }
 334  ],
 335  "metadata": {
 336   "kernelspec": {
 337    "display_name": "Ruby 2.4.0",
 338    "language": "ruby",
 339    "name": "ruby"
 340   },
 341   "language_info": {
 342    "file_extension": ".rb",
 343    "mimetype": "application/x-ruby",
 344    "name": "ruby",
 345    "version": "2.4.0"
 346   }
 347  },
 348  "nbformat": 4,
 349  "nbformat_minor": 0
 350 }