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 Python3 (judge verdict: Accepted)

x = []
y = []
for _ in range(1,10001):
    a, b = map(int,input().split())
    if a == b == 0:
        break
    x.append(a)
    y.append(b)

for x_num, y_num in zip(x,y):
    if x_num > y_num:
        x_num, y_num = y_num, x_num
    print(x_num,y_num)