
# slower version:

s = input()
for i in range(len(s)):
  if i%2 == 0:
    print(s[i], end = '')


# optimized version of the same code:

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



# slower version:

import sys



input = sys.stdin.readline



def main():

    ans = 0

    n = int(input())

    o = list(map(int, input().split()))

    l = [0]*n

    for i in range(n):

        l[o[i]-1] = i+1

    for i in range(len(l)):

        if  i != len(l)-1:

            print("{} ".format(l[i]), end='')

        else:

            print(l[i])



if __name__ == '__main__':

    main()


# optimized version of the same code:

import sys



input = sys.stdin.readline



def main():

    ans = 0

    n = int(eval(input()))

    o = list(map(int, input().split()))

    l = [0]*n

    for i in range(n):

        l[o[i]-1] = i+1

    print((" ".join(map(str,l))))

if __name__ == '__main__':

    main()
import sys

input = sys.stdin.readline


def main():
    ans = 0
    n = int(input())
    o = list(map(int, input().split()))
    l = [0] * n
    for i in range(n):
        l[o[i] - 1] = i + 1
    for i in range(len(l)):
        if i != len(l) - 1:
            print("{} ".format(l[i]), end="")
        else:
            print(l[i])


if __name__ == "__main__":
    main()

import sys

input = sys.stdin.readline


def main():
    ans = 0
    n = int(eval(input()))
    o = list(map(int, input().split()))
    l = [0] * n
    for i in range(n):
        l[o[i] - 1] = i + 1
    print((" ".join(map(str, l))))


if __name__ == "__main__":
    main()

-    n = int(input()) +    n = int(eval(input())) -    for i in range(len(l)): -        if i != len(l) - 1: -            print("{} ".format(l[i]), end="") -        else: -            print(l[i]) +    print((" ".join(map(str, l))))