print("".join(map(str, [c for i,c in enumerate(input()) if i % 2 == 0])))

print("".join([c for i,c in enumerate(input()) if i % 2 == 0]))

print("".join(map(str, [c for i, c in enumerate(input()) if i % 2 == 0])))

print("".join([c for i, c in enumerate(input()) if i % 2 == 0]))

-print("".join(map(str, [c for i, c in enumerate(input()) if i % 2 == 0]))) +print("".join([c for i, c in enumerate(input()) if i % 2 == 0]))