s = list(eval(input()))

print(("".join([s[i] for i in range(len(s)) if i%2==0])))
print((input()[::2]))
s = list(eval(input()))
print(("".join([s[i] for i in range(len(s)) if i % 2 == 0])))

print((input()[::2]))

-s = list(eval(input())) -print(("".join([s[i] for i in range(len(s)) if i % 2 == 0]))) +print((input()[::2]))