
# 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:

N,M,K = list(map(int,input().split()))



for i in range(N+1):

    for j in range(M+1):

        t = i*M + j*N - i*j*2

        if t==K:

            print('Yes')

            exit()

print('No')

# optimized version of the same code:

N,M,K = list(map(int,input().split()))



for i in range(N+1):

    for j in range(M+1):

        if i*(M-j) + j*(N-i) == K:

            print('Yes')

            exit()

print('No')
N, M, K = list(map(int, input().split()))
for i in range(N + 1):
    for j in range(M + 1):
        t = i * M + j * N - i * j * 2
        if t == K:
            print("Yes")
            exit()
print("No")

N, M, K = list(map(int, input().split()))
for i in range(N + 1):
    for j in range(M + 1):
        if i * (M - j) + j * (N - i) == K:
            print("Yes")
            exit()
print("No")

-        t = i * M + j * N - i * j * 2 -        if t == K: +        if i * (M - j) + j * (N - i) == K: