vacation

#include "bits/stdc++.h"
using namespace std;
int dp[100001][3], a[100001][3];
// vector< vector<int> > dp(100001, vector<int> (3,-1);
// vector< vector<int> > dp(100001, vector<int> (3);
// same with a
int n;

int solve(int i, int j) {

    if (i == n)return 0;
    if (dp[i][j] != -1)return dp[i][j];
    else return dp[i][j] = a[i][j] + max(solve(i + 1, (j + 1) % 3), solve(i + 1, (j + 2) % 3));
}

int main() {
    cin >> n;
    for (int i = 0; i < n; i++)
        for (int j = 0; j < 3; j++) {
            cin >> a[i][j];
            dp[i][j] = -1;
        }
    int ans = 0;
    for (int j = 0; j < 3; j++)ans = max(ans , solve(0, j));
    cout << ans << endl;
}