From 17380b005b102958fb132ea12e705e284f22f322 Mon Sep 17 00:00:00 2001 From: Neil Smith Date: Fri, 17 Mar 2017 17:51:14 +0000 Subject: [PATCH] Done puzzle 50 --- euler50.ipynb | 269 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 269 insertions(+) create mode 100644 euler50.ipynb diff --git a/euler50.ipynb b/euler50.ipynb new file mode 100644 index 0000000..c2ae98e --- /dev/null +++ b/euler50.ipynb @@ -0,0 +1,269 @@ +{ + "cells": [ + { + "cell_type": "code", + "execution_count": 12, + "metadata": { + "collapsed": false, + "scrolled": true + }, + "outputs": [ + { + "data": { + "text/plain": [ + "104743" + ] + }, + "execution_count": 12, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "load 'primes.rb'\n", + "$primes = Primes.instance\n", + "$primes[10000] # returns the 10,001st prime" + ] + }, + { + "cell_type": "code", + "execution_count": 13, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + "[2, 3, 5]" + ] + }, + "execution_count": 13, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "(0...(0+3)).map{|i| $primes[i]}" + ] + }, + { + "cell_type": "code", + "execution_count": 17, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + ":prime_slice" + ] + }, + "execution_count": 17, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "def prime_slice(start, len)\n", + " (start...(start + len)).map{|i| $primes[i]}\n", + "end" + ] + }, + { + "cell_type": "code", + "execution_count": 18, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + ":sum_primes" + ] + }, + "execution_count": 18, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "def sum_primes(start, len)\n", + " prime_slice(start, len).sum\n", + "end" + ] + }, + { + "cell_type": "code", + "execution_count": 20, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + "[2, 3, 5, 7, 11]" + ] + }, + "execution_count": 20, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "prime_slice(0, 5)" + ] + }, + { + "cell_type": "code", + "execution_count": 19, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "data": { + "text/plain": [ + "28" + ] + }, + "execution_count": 19, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "sum_primes(0, 5)" + ] + }, + { + "cell_type": "code", + "execution_count": 30, + "metadata": { + "collapsed": false, + "scrolled": true + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "0 - 2 : 5\n", + "0 - 4 : 17\n", + "0 - 6 : 41\n", + "0 - 12 : 197\n", + "0 - 14 : 281\n", + "0 - 60 : 7699\n", + "0 - 64 : 8893\n", + "0 - 96 : 22039\n", + "0 - 100 : 24133\n", + "0 - 102 : 25237\n", + "0 - 108 : 28697\n", + "0 - 114 : 32353\n", + "0 - 122 : 37561\n", + "0 - 124 : 38921\n", + "0 - 130 : 43201\n", + "0 - 132 : 44683\n", + "0 - 146 : 55837\n", + "0 - 152 : 61027\n", + "0 - 158 : 66463\n", + "0 - 162 : 70241\n", + "0 - 178 : 86453\n", + "0 - 192 : 102001\n", + "0 - 198 : 109147\n", + "0 - 204 : 116533\n", + "0 - 206 : 119069\n", + "0 - 208 : 121631\n", + "0 - 214 : 129419\n", + "0 - 216 : 132059\n", + "0 - 296 : 263171\n", + "0 - 308 : 287137\n", + "0 - 326 : 325019\n", + "0 - 328 : 329401\n", + "0 - 330 : 333821\n", + "0 - 332 : 338279\n", + "0 - 334 : 342761\n", + "0 - 342 : 360979\n", + "0 - 350 : 379667\n", + "0 - 356 : 393961\n", + "0 - 358 : 398771\n", + "0 - 426 : 581921\n", + "0 - 446 : 642869\n", + "0 - 458 : 681257\n", + "0 - 460 : 687767\n", + "0 - 464 : 700897\n", + "0 - 480 : 754573\n", + "0 - 484 : 768373\n", + "0 - 488 : 782263\n", + "0 - 512 : 868151\n", + "0 - 530 : 935507\n", + "0 - 536 : 958577\n", + "2 - 537 : 970219\n", + "2 - 539 : 978037\n", + "3 - 543 : 997651\n" + ] + }, + { + "data": { + "text/plain": [ + "[3, 543, 997651]" + ] + }, + "execution_count": 30, + "metadata": {}, + "output_type": "execute_result" + } + ], + "source": [ + "sum_limit = 10**6\n", + "\n", + "start = 0\n", + "best_start = 0\n", + "best_length = 1\n", + "while primes[start] <= sum_limit\n", + " # puts start\n", + " length = 1\n", + " sp = sum_primes(start, length)\n", + " while sp <= sum_limit\n", + " if sp.prime? && length > best_length\n", + " best_start = start\n", + " best_length = length\n", + " # puts \"#{start} - #{length} : #{sum_primes(start, length)}\"\n", + " end\n", + " length += 1\n", + " sp = sum_primes(start, length)\n", + " end\n", + " start += 1\n", + "end\n", + "[best_start, best_length, sum_primes(best_start, best_length)]" + ] + }, + { + "cell_type": "code", + "execution_count": null, + "metadata": { + "collapsed": true + }, + "outputs": [], + "source": [] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Ruby 2.4.0", + "language": "ruby", + "name": "ruby" + }, + "language_info": { + "file_extension": ".rb", + "mimetype": "application/x-ruby", + "name": "ruby", + "version": "2.4.0" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} -- 2.34.1