function vtime($time) {
    $output = '';
    foreach (array(86400 => '天', 3600 => '小时', 60 => '分', 1 => '秒') as $key => $value) {
        if ($time >= $key) $output .= floor($time/$key) . $value;
        $time %= $key;
    }
    return $output;
}