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: Wrong Answer)

input = []
loop do
  input.push(gets.split(' ').map(&:to_i))
  if input[-1][0] == 0 && input[-1][1] == 0
    input.pop
    break
  end
end

input.length.times do |i|
  x = input[i][0]
  y = input[i][1]
  if x > y
    puts '%d %d' % [y, x]
  else
    print '%d %d' % [x, y]
  end
end