def main():
    N = int(input())
    A = list(map(int, input().split()))
    B = list(map(int, input().split()))
    X = list(map(int, input().split()))
    Y = list(map(int, input().split()))

    dp_table = [0 for _ in range(N+1)]
    for idx in range(N):
        dp_table[idx+1] = (
            dp_table[idx]
            + max(
                A[idx*2] + B[idx*2+1] + Y[idx],
                B[idx*2] + A[idx*2+1] + Y[idx],
                A[idx*2] + A[idx*2+1] + X[idx],
                B[idx*2] + B[idx*2+1] + X[idx]
            )
        )

    print(dp_table[-1])


if __name__ == "__main__":
    main()