

while True:

    a, b = list(map(int, input().split()))

    

    if (a == 0) & (b == 0):

        break

    

    if a < b:

        print((a, b))

    else:

        print((b, a))

while True:

    a, b = list(map(int, input().split()))

    

    if a == 0 and b == 0:

        break

    

    if a < b:

        print((a, b))

    else:

        print((b, a))

while True:
    a, b = list(map(int, input().split()))
    if (a == 0) & (b == 0):
        break
    if a < b:
        print((a, b))
    else:
        print((b, a))

while True:
    a, b = list(map(int, input().split()))
    if a == 0 and b == 0:
        break
    if a < b:
        print((a, b))
    else:
        print((b, a))

-    if (a == 0) & (b == 0): +    if a == 0 and b == 0: