#include <vector>
#include <iostream>
#define int long long
using namespace std;

signed tempo_massimo(signed N, signed A[], signed B[])
{
    int n=N;
    vector<int> a(n),b(n);
    for(int i=0;i<n;i++){
        a[i]=A[i];
        b[i]=B[i];
    }   
    vector<vector<int>> dp(n,{0,0});
    dp[0][1]=max(a[0],b[0]);
    for(int i=1;i<n;i++){
        dp[i][0]=max(dp[i-1][0],dp[i-1][1]);
        dp[i][1]=max(max(dp[i-1][0],dp[i-1][1])+a[i],dp[i-1][0]+b[i]);
    }
    return max(dp[n-1][1],dp[n-1][0]);
}