Restructuring

solutions/ProjectEuler/104/desc.yml

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+title: Finding Fibonacci numbers for which the first and last nine digits are pandigital.
+url: http://projecteuler.net/problem=104
+
+desc: |
+  The Fibonacci sequence is defined by the recurrence relation:
+  Fn = Fn1 + Fn2, where F1 = 1 and F2 = 1.
+  It turns out that F541, which contains 113 digits, is the first Fibonacci number for which the last nine digits are 1-9 pandigital (contain all the digits 1 to 9, but not necessarily in order). And F2749, which contains 575 digits, is the first Fibonacci number for which the first nine digits are 1-9 pandigital.
+  Given that Fk is the first Fibonacci number for which the first nine digits AND the last nine digits are 1-9 pandigital, find k.
+  
+solution: |
+  Bruteforce
+
+solutions:
+  solve.php:
+    desc: Bruteforce - Sooooo slow
+    language: php

solutions/ProjectEuler/104/solve.php

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+<?php
+
+function pandigital($num) {
+	for ($i = 1; $i <= 9; $i++) {
+		if(strpos($n,(string)$i) === false) {
+			return false;
+		}
+	}
+	return true;
+}
+$var = 1;
+$k = 1;
+while(true) {
+	$k++;
+	$new = bcadd($var,$prev);
+	$prev = $var;
+	$var = $new;
+	
+	if(pandigital(substr($var,-9)) AND pandigital(substr($var,0,9))) { echo $k; die; }
+}