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)

arr = []
i=0
loop do
  a, b = gets.chomp.split(' ').map(&:to_i)
  if a == 0 && b==0
    arr.each {|i| puts i[0].to_s+' '+i[1].to_s}
    break
  else
    if a < b
      arr.push([a, b])
    else
      arr.push([b, a])
    end
  end
  i+=1
end