while True:

    (x, y) = [int(i) for i in input().split()]

    if x == y == 0:

        break



    if x < y:

        print((x, y))

    else:

        print((y, x))
while True:

    x, y = [int(i) for i in input().split()]



    if x == y == 0:

        break



    if x > y:

        x, y = y, x



    print((x, y))
while True:
    (x, y) = [int(i) for i in input().split()]
    if x == y == 0:
        break
    if x < y:
        print((x, y))
    else:
        print((y, x))

while True:
    x, y = [int(i) for i in input().split()]
    if x == y == 0:
        break
    if x > y:
        x, y = y, x
    print((x, y))

-    (x, y) = [int(i) for i in input().split()] +    x, y = [int(i) for i in input().split()] -    if x < y: -        print((x, y)) -    else: -        print((y, x)) +    if x > y: +        x, y = y, x +    print((x, y))