include bits stdc using namespace std define MAXN 100010 define MAX ma

#include <bits/stdc++.h>
using namespace std;
#define MAXN 100010
#define MAX(a,b,c) max(a,max(b,c))
#define FOR(i,s,e) for(int i=s; i<=e; i++)
int cost[MAXN][4], memo[MAXN][2][2][2][4];
int n;
class fastio {
public:
    fastio() {
        ios_base::sync_with_stdio(false);
        cout.tie(nullptr);
        cin.tie(nullptr);
    }
} __fastio;
int f(int i, int ka, int kb, int kc, int phase) {
    if(i > n) return 0;
    if(memo[i][ka][kb][kc][phase] != -1) return memo[i][ka][kb][kc][phase];
    if(ka == 1) {
        if(kb > kc) return memo[i][ka][kb][kc][phase] = f(i+1, 0, 1, 0, 1) + cost[i][1];
        else if(kc > kb) return memo[i][ka][kb][kc][phase] = f(i+1, 0, 0, 1, 1) + cost[i][1];
        else return memo[i][ka][kb][kc][phase] = max(f(i+1, 0, 1, 0, 1) + cost[i][1], f(i+1, 0, 0, 1, 1) + cost[i][1]);
    }
    if(kb == 1) {
        if(ka > kc) return memo[i][ka][kb][kc][phase] = f(i+1, 1, 0, 0, 2) + cost[i][2];
        else if(kc > ka) memo[i][ka][kb][kc][phase] = f(i+1, 0, 0, 1, 2) + cost[i][2];
        else return memo[i][ka][kb][kc][phase] = max(f(i+1, 1, 0, 0, 2) + cost[i][2], f(i+1, 0, 0, 1, 2) + cost[i][2]);
    }
    if(kc == 1) {
        if(ka > kb) return memo[i][ka][kb][kc][phase] = (i+1, 1, 0, 0, 3) + cost[i][3];
        else if(kb > ka) return memo[i][ka][kb][kc][phase] = f(i+1, 0, 1, 0, 3) + cost[i][3];
        else return memo[i][ka][kb][kc][phase] = max(f(i+1, 1, 0, 0, 3) + cost[i][3], f(i+1, 0, 1, 0, 3) + cost[i][3]);
    }
}
void solve() {
    cin >> n;
    FOR(i,1,n) {
        cin >> cost[i][1] >> cost[i][2] >> cost[i][3];
    }
    memset(memo, -1, sizeof(memo));
    cout << MAX(f(1,1,0,0,1), f(1,0,1,0,2), f(1,0,0,1,3)) << endl;
}
int main() {
  __fastio;
  solve();
  return 0;
}