
# 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:

def main():

    import sys

    input = sys.stdin.buffer.readline

    N = int(input())

    TXY = [[int(i) for i in input().split()] for j in range(N)]

    time, px, py = 0, 0, 0

    for t, x, y in TXY:

        move = abs(x-px) + abs(y-py)

        # print(move, t-time)

        if (t - time) % 2 != move % 2 or t - time < move:

            return print("No")

        time, px, py = t, x, y

    print("Yes")





if __name__ == '__main__':

    main()


# optimized version of the same code:

def main():

    import sys

    input = sys.stdin.buffer.readline

    N = int(input())

    TXY = [[int(i) for i in input().split()] for j in range(N)]

    time = 0

    px = 0

    py = 0

    for t, x, y in TXY:

        move = abs(py-y) + abs(px - x)

        if (t-time) < move or (t - time) % 2 != move % 2:

            return print("No")

        time = t

        px = x

        py = y

    print("Yes")





if __name__ == '__main__':

    main()

def main():
    import sys

    input = sys.stdin.buffer.readline
    N = int(input())
    TXY = [[int(i) for i in input().split()] for j in range(N)]
    time, px, py = 0, 0, 0
    for t, x, y in TXY:
        move = abs(x - px) + abs(y - py)
        # print(move, t-time)
        if (t - time) % 2 != move % 2 or t - time < move:
            return print("No")
        time, px, py = t, x, y
    print("Yes")


if __name__ == "__main__":
    main()

def main():
    import sys

    input = sys.stdin.buffer.readline
    N = int(input())
    TXY = [[int(i) for i in input().split()] for j in range(N)]
    time = 0
    px = 0
    py = 0
    for t, x, y in TXY:
        move = abs(py - y) + abs(px - x)
        if (t - time) < move or (t - time) % 2 != move % 2:
            return print("No")
        time = t
        px = x
        py = y
    print("Yes")


if __name__ == "__main__":
    main()

-    time, px, py = 0, 0, 0 +    time = 0 +    px = 0 +    py = 0 -        move = abs(x - px) + abs(y - py) -        # print(move, t-time) -        if (t - time) % 2 != move % 2 or t - time < move: +        move = abs(py - y) + abs(px - x) +        if (t - time) < move or (t - time) % 2 != move % 2: -        time, px, py = t, x, y +        time = t +        px = x +        py = y