#include <bits/stdc++.h>
using namespace std;

int tempo_massimo(int N, int A[], int B[]) {
    vector<long long> dp(N + 2);
    for (int i = 0; i < N; i ++) {
        dp[i + 2] = max(dp[i] + B[i], dp[i+1] + A[i]);
    }
    return max(dp[N + 1], dp[N]);
}

/*int main() {
    int A[4] = {3, 3, 3, 3};
    int B[4] = {2, 3, 1, 4};
    cout << tempo_massimo(4, A, B);
}*/