add problem 22

notebooks/problem0022.ipynb

@@ -0,0 +1,86 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "266f39d0",
+   "metadata": {},
+   "source": [
+    "# [Names Scores](https://projecteuler.net/problem=22)\n",
+    "\n",
+    "First, let's read the names into a list. We'll also strip the quotes around each name and sort them."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "2f23e8ed",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "with open(\"txt/0022_names.txt\") as f:\n",
+    "    names = f.read().split(',')\n",
+    "    \n",
+    "for (i, name) in enumerate(names):\n",
+    "    names[i] = name.strip('\"')\n",
+    "    \n",
+    "names.sort()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "947bb620",
+   "metadata": {},
+   "source": [
+    "The [`ord` function](https://docs.python.org/3/library/functions.html) returns the [Unicode](https://en.wikipedia.org/wiki/Unicode) code point of the provided character. Conveniently, the code point for `A` is 65, `B` is 66, and so on, so we can just subtract 64 to get an (uppercase) letter's number value. (These code points were chosen to be the same as [ASCII's](https://en.wikipedia.org/wiki/ASCII) for backward compatibility. [Here's a short but informative video on Unicode and UTF-8](https://www.youtube.com/watch?v=MijmeoH9LT4).)\n",
+    "\n",
+    "Add up these number values for a name, multiply by the position in the list, and sum up."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "9966edb4",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "871198282"
+      ]
+     },
+     "execution_count": 2,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "def name_score(pos, name):\n",
+    "    return pos * sum(ord(c) - 64 for c in name)\n",
+    "\n",
+    "\n",
+    "sum(name_score(i, name) for (i, name) in enumerate(names, start=1))"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "SageMath 9.5",
+   "language": "sage",
+   "name": "sagemath"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.11.2"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}