
# 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:

x = int(eval(input()))

for i in range(-200,200,1):

    for j in range(-200,200,1):

        if i**5-j**5==x:

          print((i,j))

          exit()

# optimized version of the same code:

import sys

x = int(eval(input()))

for i in range(-159,159,1):

    for j in range(-159,159,1):

        if i**5 - j**5 == x:

            print((str(i)+' '+str(j)))

            sys.exit()
x = int(eval(input()))
for i in range(-200, 200, 1):
    for j in range(-200, 200, 1):
        if i**5 - j**5 == x:
            print((i, j))
            exit()

import sys

x = int(eval(input()))
for i in range(-159, 159, 1):
    for j in range(-159, 159, 1):
        if i**5 - j**5 == x:
            print((str(i) + " " + str(j)))
            sys.exit()

+import sys + -for i in range(-200, 200, 1): -    for j in range(-200, 200, 1): +for i in range(-159, 159, 1): +    for j in range(-159, 159, 1): -            print((i, j)) -            exit() +            print((str(i) + " " + str(j))) +            sys.exit()