shorturl.php

<?php

// Author: Allex Wang (http://iallex.com)
// GistID: 1ec4083d5c3321ceb96a
// GistURL: https://gist.github.com/1ec4083d5c3321ceb96a

function shorturl($input) {
  $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'
    );
 
  $hex = md5($input);
  $hexLen = strlen($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 = 0x0000001F & $int;
      $out .= $base32[$val];
      $int = $int >> 5;
    }
 
    $output[] = $out;
  }
 
  return $output;
}

var_dump(shorturl("http://www.codesphp.com/php-category/algorithms/php-short-url-algorithm-implementation.html?utm_medium=twitter&utm_source=twitterfeed"));
var_dump(shorturl("https://raw.github.co"));
?>