<?phpfunction shorturl($url=‘‘) {$base = array (              "a" , "b" , "c" , "d" , "e" , "f" , "g" , "h" ,              "i" , "j" , "k" , "l" , "m" , "n" , "o" , "p" ,               "q" , "r" , "s" , "t" , "u" , "v" , "w" , "x" ,               "y" , "z" , "0" , "1" , "2" , "3" , "4" , "5" ,              "6" , "7" , "8" , "9" , "A" , "B" , "C" , "D" ,               "E" , "F" , "G" , "H" , "I" , "J" , "K" , "L" ,               "M" , "N" , "O" , "P" , "Q" , "R" , "S" , "T" ,              "U" , "V" , "W" , "X" , "Y" , "Z");$hex = md5($url);$hexLen = strlen($hex);$subHexLen = $hexLen / 8;$output = array();for ($i = 0; $i < $subHexLen; $i++) {    $subHex = substr ($hex, $i * 8, 8);    $int = 0x3FFFFFFF & (1 * (‘0x‘.$subHex));    $out = ‘‘;    for ($j = 0; $j < 6; $j++) {        $val = 0x0000003D & $int;//因为6个字符的每个字符有26+26+10个组合        $out .= $base[$val];        $int = $int >> 5;//取$int30位长度,每次右移5位，正好可以得到6个组    }    $output[] = $out;    }    return $output;}$urls = shorturl(‘http://www.php100.com‘);echo "<pre>";var_dump($urls);exit();?>