Problem:
Swapping Two Numbers

Write a program which reads two integers x and y, and prints them in ascending order.

Input

The input consists of multiple datasets. Each dataset consists of two integers x and y separated by a single space.

The input ends with two 0 (when both x and y are zero). Your program should not process for these terminal symbols.

Output

For each dataset, print x and y in ascending order in a line. Put a single space between x and y.

Constraints

0 ≤ x, y ≤ 10000

the number of datasets ≤ 3000

Sample Input

3 2
2 2
5 3
0 0

Sample Output

2 3
2 2
3 5

Solution in Ruby (judge verdict: Accepted)

#!/usr/bin/env ruby
# -*- coding: utf-8 -*-
      
if __FILE__ == $0
  while line = STDIN.gets
    tokens = line.chomp!.split.map!(&:to_i)
    x, y = tokens[0], tokens[1]
    break if x == 0 && y == 0

    if x > y
      x, y = y, x
    end

    puts "#{x} #{y}"
  end
end