
# 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 numpy as np



eval(input())

A = np.array(list(map(int, input().split())))



ans = 0

while(all(A%2==0)):

    A = A/2

    ans += 1



print(ans)


# optimized version of the same code:

eval(input())

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



ans = 0

while all(a%2==0 for a in A):

    A=[a/2 for a in A]

    ans += 1



print(ans)
import numpy as np

eval(input())
A = np.array(list(map(int, input().split())))
ans = 0
while all(A % 2 == 0):
    A = A / 2
    ans += 1
print(ans)

eval(input())
A = list(map(int, input().split()))
ans = 0
while all(a % 2 == 0 for a in A):
    A = [a / 2 for a in A]
    ans += 1
print(ans)

-import numpy as np - -A = np.array(list(map(int, input().split()))) +A = list(map(int, input().split())) -while all(A % 2 == 0): -    A = A / 2 +while all(a % 2 == 0 for a in A): +    A = [a / 2 for a in A]