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)

xarr = [] 
yarr = []
while true
  x, y = gets.split.map(&:to_i)
  break if x.zero? && y.zero?
  xarr.push(x)
  yarr.push(y)
end

xarr.zip(yarr) do |x, y|
  if x < y
    puts x.to_s + " " + y.to_s
  else
    puts y.to_s + " " + x.to_s
  end
end