
# 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:

H, W, K = list(map(int, input().split()))

MOD = 10 ** 9 + 7



Hd = sum([d * (H - d) * (W ** 2) for d in range(H)])

Wd = sum([d * (W - d) * (H ** 2) for d in range(W)])





# 階乗 & 逆元計算

factorial = [1]

inverse = [1]

for i in range(1, H * W + 2):

    factorial.append(factorial[-1] * i % MOD)

    inverse.append(pow(factorial[-1], MOD - 2, MOD))





ans = (Hd + Wd) * factorial[H * W - 2] * inverse[K - 2] * inverse[H * W - K] % MOD

print(ans)


# optimized version of the same code:

H, W, K = list(map(int, input().split()))

MOD = 10 ** 9 + 7



factorial = [1, 1]  # 元テーブル

inverse = [1, 1]  # 逆元テーブル

inverse_from = [0, 1]  # 逆元テーブル計算用テーブル



for i in range(2, H * W + 1):

    factorial.append((factorial[-1] * i) % MOD)

    inverse_from.append((-inverse_from[MOD % i] * (MOD // i)) % MOD)

    inverse.append((inverse[-1] * inverse_from[-1]) % MOD)





def nCr(n, r):

    if n < r or r < 0:

        return 0

    elif r == 0:

        return 1

    return factorial[n] * inverse[r] * inverse[n - r] % MOD





ans = 0

# Hについて

for d in range(1, H):

    ans += d * (H - d) * pow(W, 2, MOD) * nCr(H * W - 2, K - 2) % MOD

    ans %= MOD

# Wについて

for d in range(1, W):

    ans += d * (W - d) * pow(H, 2, MOD) * nCr(H * W - 2, K - 2) % MOD

    ans %= MOD



print((ans % MOD))

H, W, K = list(map(int, input().split()))
MOD = 10**9 + 7
Hd = sum([d * (H - d) * (W**2) for d in range(H)])
Wd = sum([d * (W - d) * (H**2) for d in range(W)])
# 階乗 & 逆元計算
factorial = [1]
inverse = [1]
for i in range(1, H * W + 2):
    factorial.append(factorial[-1] * i % MOD)
    inverse.append(pow(factorial[-1], MOD - 2, MOD))
ans = (Hd + Wd) * factorial[H * W - 2] * inverse[K - 2] * inverse[H * W - K] % MOD
print(ans)

H, W, K = list(map(int, input().split()))
MOD = 10**9 + 7
factorial = [1, 1]  # 元テーブル
inverse = [1, 1]  # 逆元テーブル
inverse_from = [0, 1]  # 逆元テーブル計算用テーブル
for i in range(2, H * W + 1):
    factorial.append((factorial[-1] * i) % MOD)
    inverse_from.append((-inverse_from[MOD % i] * (MOD // i)) % MOD)
    inverse.append((inverse[-1] * inverse_from[-1]) % MOD)


def nCr(n, r):
    if n < r or r < 0:
        return 0
    elif r == 0:
        return 1
    return factorial[n] * inverse[r] * inverse[n - r] % MOD


ans = 0
# Hについて
for d in range(1, H):
    ans += d * (H - d) * pow(W, 2, MOD) * nCr(H * W - 2, K - 2) % MOD
    ans %= MOD
# Wについて
for d in range(1, W):
    ans += d * (W - d) * pow(H, 2, MOD) * nCr(H * W - 2, K - 2) % MOD
    ans %= MOD
print((ans % MOD))

-Hd = sum([d * (H - d) * (W**2) for d in range(H)]) -Wd = sum([d * (W - d) * (H**2) for d in range(W)]) -# 階乗 & 逆元計算 -factorial = [1] -inverse = [1] -for i in range(1, H * W + 2): -    factorial.append(factorial[-1] * i % MOD) -    inverse.append(pow(factorial[-1], MOD - 2, MOD)) -ans = (Hd + Wd) * factorial[H * W - 2] * inverse[K - 2] * inverse[H * W - K] % MOD -print(ans) +factorial = [1, 1]  # 元テーブル +inverse = [1, 1]  # 逆元テーブル +inverse_from = [0, 1]  # 逆元テーブル計算用テーブル +for i in range(2, H * W + 1): +    factorial.append((factorial[-1] * i) % MOD) +    inverse_from.append((-inverse_from[MOD % i] * (MOD // i)) % MOD) +    inverse.append((inverse[-1] * inverse_from[-1]) % MOD) + + +def nCr(n, r): +    if n < r or r < 0: +        return 0 +    elif r == 0: +        return 1 +    return factorial[n] * inverse[r] * inverse[n - r] % MOD + + +ans = 0 +# Hについて +for d in range(1, H): +    ans += d * (H - d) * pow(W, 2, MOD) * nCr(H * W - 2, K - 2) % MOD +    ans %= MOD +# Wについて +for d in range(1, W): +    ans += d * (W - d) * pow(H, 2, MOD) * nCr(H * W - 2, K - 2) % MOD +    ans %= MOD +print((ans % MOD))