s = eval(input())

ans = ""

for i in range(len(s)):

    if i % 2 == 0:

        ans += s[i]

print(ans)
s=eval(input())

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

s = eval(input())
print((s[::2]))

-ans = "" -for i in range(len(s)): -    if i % 2 == 0: -        ans += s[i] -print(ans) +print((s[::2]))