N = int(eval(input()))

for _ in range(N):

    f, s = [int(eval(input())) for _ in range(2)]

    print((f+s if len(str(f+s)) <= 80 else "overflow"))
N = int(eval(input()))

for _ in range(N):

    a = int(eval(input()))

    b = int(eval(input()))

    c = a + b

    length = len(str(c))

    print(([c, "overflow"][length > 80]))



N = int(eval(input()))
for _ in range(N):
    f, s = [int(eval(input())) for _ in range(2)]
    print((f + s if len(str(f + s)) <= 80 else "overflow"))

N = int(eval(input()))
for _ in range(N):
    a = int(eval(input()))
    b = int(eval(input()))
    c = a + b
    length = len(str(c))
    print(([c, "overflow"][length > 80]))

-    f, s = [int(eval(input())) for _ in range(2)] -    print((f + s if len(str(f + s)) <= 80 else "overflow")) +    a = int(eval(input())) +    b = int(eval(input())) +    c = a + b +    length = len(str(c)) +    print(([c, "overflow"][length > 80]))