BinarySearch.php

<?php
function binarySearch($item, $arr) {

    $result = false;
    $start = 0;
    $end = count($arr) - 1;
    $iterations = 0;

    while($start <= $end) {
        $iterations++;
        $middle = (int)($start + ($end - $start) / 2);

        if ( $arr[$middle] === $item ) {
            $result = true;
            break;
        }

        if ( $arr[$middle] > $item ) {
            $end = $middle - 1;
        } else {
            $start = $middle + 1;
        }
    }

    var_dump($iterations);
    return $result;
}