Code for http://stackoverflow.com/questions/5782646/switching-from-php-to-rails-need-help-translating-url-shortener

_results.txt

$ ./php.php 
578260286050
58677803167
3520668190027
8542342158446695842
$ ./ruby.rb 
578260286050
58677803167
3520668190027
8542342158446695842

php.php

#!/usr/bin/env php
<?php

function getIDFromShortenedURL1 ($string, $base = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ')
{
    $length = strlen($base);
    $size = strlen($string) - 1;
    $string = str_split($string);

    $out = strpos($base, array_pop($string));

    foreach($string as $i => $char)
    {
        $out += strpos($base, $char) * pow($length, $size - $i);
    }
    return $out;
}

echo getIDFromShortenedURL1("abcdefg") . "\n";
echo getIDFromShortenedURL1("1234567") . "\n";
echo getIDFromShortenedURL1("ZYXWVUT") . "\n";
echo getIDFromShortenedURL1("ab2165AZefg") . "\n";

?>

ruby.rb

#!/usr/bin/env ruby

def getIDFromShortenedURL1(string, base = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ')
  length = base.length         # $length = strlen($base);
  size   = string.length - 1   # $size   = strlen($string) - 1;
  string = string.split ''     # $string = str_split($string);

  out = base.index string.pop  # $out = strpos($base, array_pop($string))

  string.each_with_index do |char, i|  # foreach($string as $i => $char);
    # $out += strpos($base, $char) * pow($length, $size - $i);
    out << base.index(char) * (length ** (size - i))
  end
  out # return $out;
end

puts getIDFromShortenedURL1('abcdefg')
puts getIDFromShortenedURL1('1234567')
puts getIDFromShortenedURL1('ZYXWVUT')
puts getIDFromShortenedURL1('ab2165AZefg')