<?php set_time_limit(0); /* If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000. */ # first lets install some useful shit. $max=1000; $array = array(); $id=0; for($loop=1;$loop < $max;$loop++) { if(($loop % 3) == 0) { $array[$id] = $loop; $id++; } elseif(($loop % 5) == 0) { $array[$id] = $loop; $id++; } } foreach($array as $id => $v) { $c += $v; } echo("Vastus: ".$c); ?>