{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Simple brute force search :)."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "70600674"
      ]
     },
     "execution_count": 33,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "matrix = \"\"\"08 02 22 97 38 15 00 40 00 75 04 05 07 78 52 12 50 77 91 08\n",
    "49 49 99 40 17 81 18 57 60 87 17 40 98 43 69 48 04 56 62 00\n",
    "81 49 31 73 55 79 14 29 93 71 40 67 53 88 30 03 49 13 36 65\n",
    "52 70 95 23 04 60 11 42 69 24 68 56 01 32 56 71 37 02 36 91\n",
    "22 31 16 71 51 67 63 89 41 92 36 54 22 40 40 28 66 33 13 80\n",
    "24 47 32 60 99 03 45 02 44 75 33 53 78 36 84 20 35 17 12 50\n",
    "32 98 81 28 64 23 67 10 26 38 40 67 59 54 70 66 18 38 64 70\n",
    "67 26 20 68 02 62 12 20 95 63 94 39 63 08 40 91 66 49 94 21\n",
    "24 55 58 05 66 73 99 26 97 17 78 78 96 83 14 88 34 89 63 72\n",
    "21 36 23 09 75 00 76 44 20 45 35 14 00 61 33 97 34 31 33 95\n",
    "78 17 53 28 22 75 31 67 15 94 03 80 04 62 16 14 09 53 56 92\n",
    "16 39 05 42 96 35 31 47 55 58 88 24 00 17 54 24 36 29 85 57\n",
    "86 56 00 48 35 71 89 07 05 44 44 37 44 60 21 58 51 54 17 58\n",
    "19 80 81 68 05 94 47 69 28 73 92 13 86 52 17 77 04 89 55 40\n",
    "04 52 08 83 97 35 99 16 07 97 57 32 16 26 26 79 33 27 98 66\n",
    "88 36 68 87 57 62 20 72 03 46 33 67 46 55 12 32 63 93 53 69\n",
    "04 42 16 73 38 25 39 11 24 94 72 18 08 46 29 32 40 62 76 36\n",
    "20 69 36 41 72 30 23 88 34 62 99 69 82 67 59 85 74 04 36 16\n",
    "20 73 35 29 78 31 90 01 74 31 49 71 48 86 81 16 23 57 05 54\n",
    "01 70 54 71 83 51 54 69 16 92 33 48 61 43 52 01 89 19 67 48\"\"\"\n",
    "\n",
    "matrix = [[int(n) for n in l.split(' ')] for l in matrix.split('\\n')]\n",
    "\n",
    "maximum = 0\n",
    "\n",
    "for row in range(20):\n",
    "    for col in range(16):\n",
    "        # right →\n",
    "        p = 1\n",
    "        for c in range(col, col+4):\n",
    "            p *= matrix[row][c]\n",
    "        maximum = max(p, maximum)\n",
    "    if row <= 16: \n",
    "        for col in range(16):\n",
    "            # down right diagonal ↘\n",
    "            p = 1\n",
    "            for i in range(4):\n",
    "                p *= matrix[row+i][col+i]\n",
    "            maximum = max(p, maximum)\n",
    "        for col in range(20):\n",
    "            # down ↓\n",
    "            p = 1\n",
    "            for r in range(row, row+4):\n",
    "                p *= matrix[r][col]\n",
    "            maximum = max(p, maximum)\n",
    "        for col in range(4, 20):\n",
    "            # down left diagonal ↙\n",
    "            p = 1\n",
    "            for i in range(4):\n",
    "                p *= matrix[row+i][col-i]\n",
    "            maximum = max(p, maximum)\n",
    "        \n",
    "\n",
    "maximum"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
 ],
 "metadata": {
  "kernelspec": {
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   "language": "python",
   "name": "python3"
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  "language_info": {
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    "name": "ipython",
    "version": 3
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   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.7.4"
  },
  "title": "Largest product in a grid"
 },
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