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)

while true
  s = ""
  a, b = gets.split.map(&:to_i)
  if (a <=> b) == 1
    s = "#{b} #{a}"
  elsif (a <=> b) == 0
    break
  elsif (a <=> b) == -1
    s = "#{a} #{b}"
  end
  puts s
end