{
 "metadata": {
  "name": ""
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "markdown",
     "source": [
      "A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 \u00d7 99.\n",
      "\n",
      "Find the largest palindrome made from the product of two 3-digit numbers."
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "class Integer\n",
      "  def palindromic?\n",
      "    self.to_s == self.to_s.reverse\n",
      "  end\n",
      "end\n",
      "\n",
      "12321.palindromic?"
     ],
     "language": "python",
     "outputs": [
      {
       "output_type": "pyout",
       "prompt_number": 4,
       "text": [
        "true"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "result = []\n",
      "\n",
      "(111..999).lazy.each do |x|\n",
      "  (111...999).lazy.each do |y|\n",
      "    temp = x * y\n",
      "    result << temp if temp.palindromic?\n",
      "  end\n",
      "end\n",
      "\n",
      "result.max"
     ],
     "language": "python",
     "outputs": [
      {
       "output_type": "pyout",
       "prompt_number": 8,
       "text": [
        "906609"
       ]
      }
     ],
     "prompt_number": 8
    }
   ]
  }
 ]
}