
# 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,t=int(input()),list(map(int,input().split()));T=sum(t)

print(*[T-t[i-1]+j for i,j in [list(map(int,input().split())) for _ in range(int(input()))]],sep='\n')


# optimized version of the same code:

input();t=list(map(int,input().split()));T=sum(t)

print(*[T-t[i-1]+j for i,j in [list(map(int,input().split())) for _ in range(int(input()))]],sep='\n')

n, t = int(input()), list(map(int, input().split()))
T = sum(t)
print(
    *[
        T - t[i - 1] + j
        for i, j in [list(map(int, input().split())) for _ in range(int(input()))]
    ],
    sep="\n"
)

input()
t = list(map(int, input().split()))
T = sum(t)
print(
    *[
        T - t[i - 1] + j
        for i, j in [list(map(int, input().split())) for _ in range(int(input()))]
    ],
    sep="\n"
)

-n, t = int(input()), list(map(int, input().split())) +input() +t = list(map(int, input().split()))