
# 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:

from math import factorial

N = int(eval(input()))

print((factorial(N) % (10**9 + 7)))

# optimized version of the same code:

from math import factorial

N = int(eval(input()))

ans = 1

for i in range(1,N+1):

    ans *= i % (10**9 + 7)

    ans %= 10**9 + 7

print(ans)
from math import factorial

N = int(eval(input()))
print((factorial(N) % (10**9 + 7)))

from math import factorial

N = int(eval(input()))
ans = 1
for i in range(1, N + 1):
    ans *= i % (10**9 + 7)
    ans %= 10**9 + 7
print(ans)

-print((factorial(N) % (10**9 + 7))) +ans = 1 +for i in range(1, N + 1): +    ans *= i % (10**9 + 7) +    ans %= 10**9 + 7 +print(ans)