Solved ProjectEuler/004

ProjectEuler/004/desc.yml

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+title: Find the largest palindrome made from the product of two 3-digit numbers.
+url: http://projecteuler.net/problem=4
+
+desc: |
+  A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91  99.
+  Find the largest palindrome made from the product of two 3-digit numbers.
+  
+solution: |
+  See code
+
+solutions:
+  solve.php:
+    desc: Basic solution
+    language: php
+  solve.rb:
+    desc: Basic solution in Ruby
+    language: ruby

ProjectEuler/004/solve.php

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+<?php
+$max = 0;
+for($num1 = 1000; $num1>100; $num1--) {
+	for($num2 = 1000; $num2>100; $num2--) {
+		$sum = $num1 * $num2;
+		
+		//Check if palindrome 
+		if($sum > $max AND strrev($sum) == $sum)
+			$max = $sum;
+			
+	}
+}
+echo $max;

ProjectEuler/004/solve.rb

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+max = 0;
+(100..1000).each do |num1|
+	(100..1000).each do |num2|
+		sum = num1 * num2
+		if( sum > max and sum.to_s.reverse  == sum.to_s) 
+			max = sum
+		end
+	end
+end
+print max