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)

x_arr = Array.new
y_arr = Array.new
loop do
  x,y = gets.chomp.split(' ').map{|x| x.to_i}
  break if x == 0 && y == 0
  x_arr << x
  y_arr << y
end

i=0
while i < x_arr.size
  if x_arr[i] < y_arr[i]
      puts "#{x_arr[i]} #{y_arr[i]}"
  else
      puts "#{y_arr[i]} #{x_arr[i]}"
  end
  i=i+1
end