
# 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:

import numpy as np

N = int(eval(input()))

plan = np.array([[0, 0, 0]] + [list(map(int, input().split())) for i in range(N)])



diff = np.diff(plan, axis = 0)



def is_possible(t, x, y):

    if (t + x + y) % 2 == 0 and abs(x) + abs(y) <= t:

        return True

    else:

        return False



for i in range(N):

    ti, xi, yi = diff[i]

    if not is_possible(ti, xi, yi):

        print('No')

        exit()

print('Yes')

# optimized version of the same code:

N = int(eval(input()))

plan = [[0, 0, 0]] + [list(map(int, input().split())) for _ in range(N)]

diff = [[plan[i + 1][j] - plan[i][j] for j in range(3)] for i in range(N)]



def is_possible(t, x, y):

    if (t + x + y) % 2 == 0 and abs(x) + abs(y) <= t:

        return True

    else:

        return False



for i in range(N):

    ti, xi, yi = diff[i]

    if not is_possible(ti, xi, yi):

        print('No')

        exit()

print('Yes')
import numpy as np

N = int(eval(input()))
plan = np.array([[0, 0, 0]] + [list(map(int, input().split())) for i in range(N)])
diff = np.diff(plan, axis=0)


def is_possible(t, x, y):
    if (t + x + y) % 2 == 0 and abs(x) + abs(y) <= t:
        return True
    else:
        return False


for i in range(N):
    ti, xi, yi = diff[i]
    if not is_possible(ti, xi, yi):
        print("No")
        exit()
print("Yes")

N = int(eval(input()))
plan = [[0, 0, 0]] + [list(map(int, input().split())) for _ in range(N)]
diff = [[plan[i + 1][j] - plan[i][j] for j in range(3)] for i in range(N)]


def is_possible(t, x, y):
    if (t + x + y) % 2 == 0 and abs(x) + abs(y) <= t:
        return True
    else:
        return False


for i in range(N):
    ti, xi, yi = diff[i]
    if not is_possible(ti, xi, yi):
        print("No")
        exit()
print("Yes")

-import numpy as np - -plan = np.array([[0, 0, 0]] + [list(map(int, input().split())) for i in range(N)]) -diff = np.diff(plan, axis=0) +plan = [[0, 0, 0]] + [list(map(int, input().split())) for _ in range(N)] +diff = [[plan[i + 1][j] - plan[i][j] for j in range(3)] for i in range(N)]