Solved ProjectEuler/012: php, ruby, c

ProjectEuler/012/desc.yml

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+title: What is the value of the first triangle number to have over five hundred divisors?
+url: http://projecteuler.net/problem=12
+
+desc: |
+  The sequence of triangle numbers is generated by adding the natural numbers. So the 7th triangle number would be 1 + 2 + 3 + 4 + 5 + 6 + 7 = 28. The first ten terms would be:
+  1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
+  Let us list the factors of the first seven triangle numbers:
+  1: 1
+  3: 1,3
+  6: 1,2,3,6
+  10: 1,2,5,10
+  15: 1,3,5,15
+  21: 1,3,7,21
+  28: 1,2,4,7,14,28
+  We can see that 28 is the first triangle number to have over five divisors.
+  What is the value of the first triangle number to have over five hundred divisors?
+  
+solution: |
+  Bruteforce - Still kinda slow - Guessing it could be improved
+
+solutions:
+  solve.php:
+    desc: Basic solution
+    language: php
+  solve.rb:
+    desc: Basic solution
+    language: ruby
+  solve.c:
+    desc: ANSI C solution compiled with TCC
+    language: c

ProjectEuler/012/solve.c

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+#include <stdio.h>
+#include <math.h>
+
+int main( )
+{
+	long num = 3;
+	long tri_add = 2;
+	long div;
+	int divisors;
+	int max = 0;
+	do
+	{
+		num += ++tri_add;
+		divisors = 2;
+		int square_root = sqrt(num);
+		for(div = 2; div <= square_root; div++)
+		{
+			if(num % div == 0)
+				divisors+=2;
+		}
+	} while(divisors <= 500);
+	printf( "%i", num );
+}

ProjectEuler/012/solve.php

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+<?php
+$num = 3;
+$tri_add = 2;
+do {
+	$num += ++$tri_add;
+	$divisors = 2;
+	$square_root = sqrt($num);
+	for($div = 2; $div <= $square_root; $div++) {
+		if($num % $div == 0)
+			$divisors+= 2;
+	}
+} while ($divisors <= 500);
+echo $num;

ProjectEuler/012/solve.rb

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+num = 3;
+tri_add = 2;
+begin
+tri_add += 1
+	num += tri_add
+	
+	divisors = 2;
+	square_root = Math.sqrt(num);
+	div = 2
+	while(div <= square_root) 
+		if(num % div == 0)
+			divisors += 2;
+		end
+		div += 1
+	end
+end until (divisors > 500);
+puts num;