PHP中实现冒泡排序和快速排序算法示例

function bubble_sort($array) {
    $count = count($array);
    if ($count <= 0) return false;
    for ($i = 0; $i < $count; $i++) {
        for ($j = $count - 1; $j > $i; $j & ndash;) {
            if ($array[$j] < $array[$j - 1]) {
                $tmp = $array[$j];
                $array[$j] = $array[$j - 1];
                $array[$j - 1] = $tmp;
            }
        }
    }
    return $array;
}
function quick_sort($array) {
    if (count($array) <= 1) return $array;
    $key = $array[0];
    $left_arr = $right_arr = array();
    foreach ($array as $val) {
        if ($val < = $key) $left_arr[] = $val;
        else $right_arr[] = $val;
    }
    $left_arr = quick_sort($left_arr);
    $right_arr = quick_sort($right_arr);
    return array_merge($left_arr, array(
        $key
    ) , $right_arr);
}

function bin_sch($array, $low, $high, $k) {
    if ($low <= $high) {
        $mid = intval(($low + $high) / 2);
        if ($array[$mid] == $k) {
            return $mid;
        } elseif ($k < $array[$mid]) {
            return bin_sch($array, $low, $mid - 1, $k);
        } else {
            return bin_sch($array, $mid + 1, $high, $k);
        }
    }
    return -1;
}
function seq_sch($array, $n, $k) {
    $array[$n] = $k;
    for ($i = 0; $i < $n; $i++) {
        if ($array[$i] == $k) {
            break;
        }
    }
    if ($i < $n) {
        return $i;
    } else {
        return -1;
    }
}

function array_sort($arr, $keys, $order = 0) {
    if (!is_array($arr)) {
        return false;
    }
    $keysvalue = array();
    foreach ($arr as $key => $val) {
        $keysvalue[$key] = $val[$keys];
    }
    if ($order == 0) {
        asort($keysvalue);
    } else {
        arsort($keysvalue);
    }
    reset($keysvalue);
    foreach ($keysvalue as $key => $vals) {
        $keysort[$key] = $key;
    }
    $new_array = array();
    foreach ($keysort as $key => $val) {
        $new_array[$key] = $arr[$val];
    }
    return $new_array;
}