# -*- coding: utf-8 -*-



s = eval(input())

sList = list(s)



output = ""



for i in range(len(sList)):

    if i%2 == 0:

        output += sList[i]



print(output)

        

        
s = eval(input())



print((s[::2]))

# -*- coding: utf-8 -*-
s = eval(input())
sList = list(s)
output = ""
for i in range(len(sList)):
    if i % 2 == 0:
        output += sList[i]
print(output)

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

-# -*- coding: utf-8 -*- -sList = list(s) -output = "" -for i in range(len(sList)): -    if i % 2 == 0: -        output += sList[i] -print(output) +print((s[::2]))