php生成短网址

<?php
/**
* Created by PhpStorm.
* User: yangyulong/anziguoer@sina.com
* Date: 2015/5/28
* Time: 15:55
*/
function shortUrl($url){
$base32 = 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'
);

$hex = md5($url);
$hexLength = strlen($hex);
$subHexLen = $hexLength / 8;

$output = array();
for ($i = 0; $i < $subHexLen; $i++) {
//每循环一次取到8位
$subHex = substr ($hex, $i * 8, 8);
$int = 0x3FFFFFFF & (1 * ('0x'.$subHex));
$out = '';

for ($j = 0; $j < 6; $j++) {
$val = 0x0000001F & $int;
$out .= $base32[$val];
$int = $int >> 5;
}

$output[] = $out;
}

return $output;
}

function shortUrl2($url){
$result = sprintf("%u",crc32($url));
$show = '';
while($result  >0){
$s = $result % 62;
if($s > 35){
$s=chr($s+61);
}elseif($s>9 && $s<=35){
$s=chr($s+55);
}
$show .= $s;
$result = floor($result / 62);
}

return $show;
}

echo shortUrl2('http://baidu.com');