Project Euler: Problem 2 – PHP Solution

Problem 2

Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:

1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...

By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.

Solution1: 

<?php$fib1 = 1;$fib2 = 2;$temp = 0;$sum =0;
while($temp<=4000000){ $temp = $fib2; $sum = ($temp%2==0) ? ($sum + $temp) : $sum ; $temp = $fib1 + $fib2; $fib1 = $fib2; $fib2 = $temp;} echo $sum;