Binary search

binary_search.php

/**
 * @param Integer[] $nums
 * @param Integer $target
 * @return Integer
 */
function search(array $nums, int $target): int {
    $left = 0;
    $right = count($nums) - 1;

    while ($left <= $right) {
        $middle = $left + (($right - $left) / 2);
        $middle = (int)$middle;

        if ($nums[$middle] === $target) {
            return $middle;
        }

        if ($target < $nums[$middle]) {
            $right = $middle - 1;
        } else {
            $left = $middle + 1;
        }
    }

    return -1;
}