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)

catch(:label) do

  while line = gets  
    throw :label if line == "0 0\n"
    a = line.chomp.split(" ")

    p_0 = a[0].to_i
    p_1 = a[1].to_i
    if p_0 > p_1
      a[0] = p_1
      a[1] = p_0
    else
      a[0] = p_0
      a[1] = p_1
    end
    puts  a[0].to_s + " " + a[1].to_s + "\n"    
  end
end