s = eval(input())

ans = ''

for i in range(0,len(s),2):

    ans += s[i]

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

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

s = eval(input())
print((s[0 : len(s) : 2]))

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