gistfile1.rb

class String
  BASE62_PRIMITIVES = {
    "0" => 0, "1" => 1, "2" => 2, "3" => 3, "4" => 4, "5" => 5, "6" => 6, "7" => 7, "8" => 8, "9" => 9,
    "A" => 10, "B" => 11, "C" => 12, "D" => 13, "E" => 14, "F" => 15, "G" => 16, "H" => 17, "I" => 18, "J" => 19,
    "K" => 20, "L" => 21, "M" => 22, "N" => 23, "O" => 24, "P" => 25, "Q" => 26, "R" => 27, "S" => 28, "T" => 29,
    "U" => 30, "V" => 31, "W" => 32, "X" => 33, "Y" => 34, "Z" => 35, "a" => 36, "b" => 37, "c" => 38, "d" => 39,
    "e" => 40, "f" => 41, "g" => 42, "h" => 43, "i" => 44, "j" => 45, "k" => 46, "l" => 47, "m" => 48, "n" => 49,
    "o" => 50, "p" => 51, "q" => 52, "r" => 53, "s" => 54, "t" => 55, "u" => 56, "v" => 57, "w" => 58, "x" => 59,
    "y" => 60, "z" => 61
  }
  
  def base62_decode
    i = 0
    i_out = 0
    self.split(//).reverse.each do |c|
      place = BASE62_PRIMITIVES.size ** i
      i_out += BASE62_PRIMITIVES[c] * place
      i += 1
    end
    i_out
  end
end


class Integer
  BASE62_PRIMITIVES = ('0'..'9').to_a + ('A'..'Z').to_a + ('a'..'z').to_a
  
  def base62_encode
     number = self
     result = ''
     while(number != 0)
        result = BASE62_PRIMITIVES[number % BASE62_PRIMITIVES.size ].to_s + result
        number /= BASE62_PRIMITIVES.size
     end
    result
  end
end