advent20.ipynb

   1 {
   2  "cells": [
   3   {
   4    "cell_type": "code",
   5    "execution_count": 1,
   6    "metadata": {
   7     "collapsed": true
   8    },
   9    "outputs": [],
  10    "source": [
  11     "target = 33100000"
  12    ]
  13   },
  14   {
  15    "cell_type": "code",
  16    "execution_count": 2,
  17    "metadata": {
  18     "collapsed": true
  19    },
  20    "outputs": [],
  21    "source": [
  22     "import collections"
  23    ]
  24   },
  25   {
  26    "cell_type": "code",
  27    "execution_count": 3,
  28    "metadata": {
  29     "collapsed": false
  30    },
  31    "outputs": [
  32     {
  33      "data": {
  34       "text/plain": [
  35        "defaultdict(<class 'int'>, {})"
  36       ]
  37      },
  38      "execution_count": 3,
  39      "metadata": {},
  40      "output_type": "execute_result"
  41     }
  42    ],
  43    "source": [
  44     "houses = collections.defaultdict(int)\n",
  45     "houses"
  46    ]
  47   },
  48   {
  49    "cell_type": "code",
  50    "execution_count": 4,
  51    "metadata": {
  52     "collapsed": true
  53    },
  54    "outputs": [],
  55    "source": [
  56     "for elf in range(1, target // 10 + 1):\n",
  57     "    for house in range(elf, target // 10 + 1, elf):\n",
  58     "        houses[house] += elf * 10"
  59    ]
  60   },
  61   {
  62    "cell_type": "code",
  63    "execution_count": 5,
  64    "metadata": {
  65     "collapsed": false
  66    },
  67    "outputs": [
  68     {
  69      "data": {
  70       "text/plain": [
  71        "[(1, 10),\n",
  72        " (2, 30),\n",
  73        " (3, 40),\n",
  74        " (4, 70),\n",
  75        " (5, 60),\n",
  76        " (6, 120),\n",
  77        " (7, 80),\n",
  78        " (8, 150),\n",
  79        " (9, 130)]"
  80       ]
  81      },
  82      "execution_count": 5,
  83      "metadata": {},
  84      "output_type": "execute_result"
  85     }
  86    ],
  87    "source": [
  88     "[(h, houses[h]) for h in range(1, 10)]"
  89    ]
  90   },
  91   {
  92    "cell_type": "code",
  93    "execution_count": 6,
  94    "metadata": {
  95     "collapsed": false
  96    },
  97    "outputs": [
  98     {
  99      "data": {
 100       "text/plain": [
 101        "776160"
 102       ]
 103      },
 104      "execution_count": 6,
 105      "metadata": {},
 106      "output_type": "execute_result"
 107     }
 108    ],
 109    "source": [
 110     "min(h for h in houses if houses[h] >= target)"
 111    ]
 112   },
 113   {
 114    "cell_type": "code",
 115    "execution_count": 7,
 116    "metadata": {
 117     "collapsed": false
 118    },
 119    "outputs": [
 120     {
 121      "data": {
 122       "text/plain": [
 123        "defaultdict(<class 'int'>, {})"
 124       ]
 125      },
 126      "execution_count": 7,
 127      "metadata": {},
 128      "output_type": "execute_result"
 129     }
 130    ],
 131    "source": [
 132     "houses2 = collections.defaultdict(int)\n",
 133     "houses2"
 134    ]
 135   },
 136   {
 137    "cell_type": "code",
 138    "execution_count": null,
 139    "metadata": {
 140     "collapsed": true
 141    },
 142    "outputs": [],
 143    "source": [
 144     "for elf in range(1, target // 10 + 1):\n",
 145     "    for house in range(1, 51):\n",
 146     "        houses2[elf * house] += elf * 11"
 147    ]
 148   },
 149   {
 150    "cell_type": "code",
 151    "execution_count": null,
 152    "metadata": {
 153     "collapsed": false
 154    },
 155    "outputs": [],
 156    "source": [
 157     "min(h for h in houses2 if houses2[h] >= target)"
 158    ]
 159   },
 160   {
 161    "cell_type": "code",
 162    "execution_count": null,
 163    "metadata": {
 164     "collapsed": true
 165    },
 166    "outputs": [],
 167    "source": []
 168   }
 169  ],
 170  "metadata": {
 171   "kernelspec": {
 172    "display_name": "Python 3",
 173    "language": "python",
 174    "name": "python3"
 175   },
 176   "language_info": {
 177    "codemirror_mode": {
 178     "name": "ipython",
 179     "version": 3
 180    },
 181    "file_extension": ".py",
 182    "mimetype": "text/x-python",
 183    "name": "python",
 184    "nbconvert_exporter": "python",
 185    "pygments_lexer": "ipython3",
 186    "version": "3.4.3"
 187   }
 188  },
 189  "nbformat": 4,
 190  "nbformat_minor": 0
 191 }