
# 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 A in range(-200, 200):

    for B in range(-200, 200):

        if A**5 - B**5 == X:

            print((A, B))

            break

    else:

        continue

    break

# optimized version of the same code:

X = int(eval(input()))

for A in range(-150, 150):

    for B in range(-150, 150):

        if A**5 - B**5 == X:

            print((A, B))

            break

    else:

        continue

    break
X = int(eval(input()))
for A in range(-200, 200):
    for B in range(-200, 200):
        if A**5 - B**5 == X:
            print((A, B))
            break
    else:
        continue
    break

X = int(eval(input()))
for A in range(-150, 150):
    for B in range(-150, 150):
        if A**5 - B**5 == X:
            print((A, B))
            break
    else:
        continue
    break

-for A in range(-200, 200): -    for B in range(-200, 200): +for A in range(-150, 150): +    for B in range(-150, 150):