X-Git-Url: https://git.njae.me.uk/?a=blobdiff_plain;f=advent20.ipynb;fp=advent20.ipynb;h=9b5dbfb5b074a730d3ae557f5dc7dd6241ed49cc;hb=f0197028478b8fbc529908c44434c4e1cd3c7780;hp=0000000000000000000000000000000000000000;hpb=b469fd3d9d90834db8371833b812191dc19a718b;p=advent-of-code-15.git

diff --git a/advent20.ipynb b/advent20.ipynb
new file mode 100644
index 0000000..9b5dbfb
--- /dev/null
+++ b/advent20.ipynb
@@ -0,0 +1,191 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "target = 33100000"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "import collections"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "defaultdict(<class 'int'>, {})"
+      ]
+     },
+     "execution_count": 3,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "houses = collections.defaultdict(int)\n",
+    "houses"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "for elf in range(1, target // 10 + 1):\n",
+    "    for house in range(elf, target // 10 + 1, elf):\n",
+    "        houses[house] += elf * 10"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "[(1, 10),\n",
+       " (2, 30),\n",
+       " (3, 40),\n",
+       " (4, 70),\n",
+       " (5, 60),\n",
+       " (6, 120),\n",
+       " (7, 80),\n",
+       " (8, 150),\n",
+       " (9, 130)]"
+      ]
+     },
+     "execution_count": 5,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "[(h, houses[h]) for h in range(1, 10)]"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "776160"
+      ]
+     },
+     "execution_count": 6,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "min(h for h in houses if houses[h] >= target)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "defaultdict(<class 'int'>, {})"
+      ]
+     },
+     "execution_count": 7,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "houses2 = collections.defaultdict(int)\n",
+    "houses2"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "for elf in range(1, target // 10 + 1):\n",
+    "    for house in range(1, 51):\n",
+    "        houses2[elf * house] += elf * 11"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "min(h for h in houses2 if houses2[h] >= target)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.4.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}