[RUBY] Number Conversion

#===============================================================================
# Methods for conversion to binary
#   conversion_timer  : gets the time taken to perform conversion. Also acts as
#                       a block handler for the conversion.
#   decimal_binary(n) : converts a decimal number to a binary number, n being
#                       the number for conversion.
#   binary_decimal(n) : converts a binary number to a decimal number, n being
#                       the number for conversion.
#   unary_decimal(n)  : converts a unary number to a decimal number, n being
#                       the number for conversion.
#   decimal_unary(n)  : converts a decimal number to a unary number, n being
#                       the number for conversion.
#===============================================================================

def conversion_timer(&proc)
  started = Time.now
  yield if block_given?
  stopped = Time.now
  res = stopped - started
  res
end

def decimal_binary(n)
  conversion_timer {
    res = []
    while n != 0
      new_n = n >> 1
      res << ((n == new_n << 1) ? '0' : '1')
      n = new_n
    end
    n = res.reverse.join.to_i
  }
  n
end

def binary_decimal(n)
  conversion_timer {
    res = 0
    exp = 1
    missing = 0
    n.to_s.reverse.each_byte { |s|
      if s == 49
        exp <<= missing
        res += exp
        missing = 1
      else
        missing += 1
      end
    }
    n = res
  }
  n
end

def unary_decimal(n)
  n.to_s.size
end

def decimal_unary(n)
  s = ''
  n.times do s += '1' end
  s
end