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)

tmp = []
cnt = "0"
while cnt != [0, 0]
  i = gets.chomp.split.map(&:to_i)
  tmp.push(i)
  tmp.flatten!
  cnt = i
end
p "tmp = #{tmp}"

num_of_element = -1 + tmp.length/2
# tmp.delete(tmp.length)
p "num_of_element = #{num_of_element}"
p "tmp = #{tmp}"

i = 0
num_of_element.times do
  x = tmp[i]
  y = tmp[i+1]
  if x <= y
    puts "#{x} #{y}"
  else
    puts "#{y} #{x}"
  end
  i = i + 2
end