Problem 1 of Project Euler

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.

The Answer

233168

Execution Time

1.7998ms

Source Code

  1. <?php
  2. /**
  3.  *  Function that returns answer for problem 1 of Project Euler.
  4.  *  @return $sum
  5.  */
  6.     function pj1()
  7.     {
  8.         list( $a, $b, $sum ) = array( 3, 5, 0);
  9.         for ( $i = 0; $i < 1000; $i++ )
  10.         {
  11.             if( ($i%$a == 0) || ($i%$b == 0))
  12.                 $sum += $i;
  13.         }
  14.         return $sum;
  15.     }
  16.  
  17.     $answer = pj1();
  18. ?>
<?php
/**
 *  Function that returns answer for problem 1 of Project Euler.
 *  @return $sum
 */
    function pj1()
    {
		list( $a, $b, $sum ) = array( 3, 5, 0);
		for ( $i = 0; $i < 1000; $i++ )
		{
			if( ($i%$a == 0) || ($i%$b == 0))
				$sum += $i;
		}
		return $sum;
    }
 
    $answer = pj1();
?>

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