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

                            #define FOR(i,a,b) for(int i = (a); i < (b); i++)
                            #define rep(i,n) FOR(i,0,n)
                            #define RFOR(i,b,a) for(int i = (b) - 1; i>= (a); i--)
                            #define ITER(it, a) for(typeof(a.begin()) it = a.begin(); it != a.end(); it++)
                            #define FILL(a, value) memset(a, value, sizeof(a)

                            #define SZ(a) (int)a.size()
                            #define ALL(a) a.begin(), a.end()
                            #define PB push_back
                            #define MP make_pair
                            #define er erase
                            #define in insert
                            #define f first
                            #define s second



                            typedef  long long LL;
                            typedef vector<int> VI;
                            typedef vector<LL > VL;
                            typedef vector<vector<int > > VVI;
                            typedef vector<vector<LL>> VVL;
                            typedef vector <vector<pair<int, int >> >VVPI;
                            typedef vector<vector<pair<LL, LL >> >VVPL;
                            typedef vector<pair<LL, LL >> PL;
                            typedef vector<PL> VPL;
                            typedef pair<int, int> PII;
                            typedef vector<PII> VPI;

                            const double PI = acos(-1.0);
                            const int INF = 1e9;
                            const LL LINF = (LL)1e18;

                            const double EPS = 1e-7;
                            const int MAS =  3 *1e5 + 10;
                            const int mod = 998244353;
                            const int MOD =1e9+7;
                            const int LOG= 19;
                            const int ar = 1e5 +100;
                            const int MAX = 1e6 + 1e2;
                         int dp[ar][3];
                         int a[ar][3];
                        int main() {
                            ios_base::sync_with_stdio(false);
                            cin.tie(NULL);
                             int n;
                             cin >> n;

                             rep(i,n)
                             {
                                 cin >> a[i][0] >> a[i][1] >> a[i][2];
                             }
                             dp[0][0] = a[0][0];
                             dp[0][1] = a[0][1];
                             dp[0][2] = a[0][2];
                             FOR(i,1,n)
                             {
                                 rep(j,3)
                                 {
                                     rep(k,3) {
                                         if (k == j)continue;
                                         dp[i][j] = max(dp[i][j],dp[i - 1][k] + a[i][j]);
                                     }
                                 }
                             }
                          //   cout << max({dp[n-1][0],dp[n-1][1],dp[n-1][2]}) << endl;
                             cout << *max_element(dp[n-1],dp[n-1] + 3) ;
                            }

















































Measured memory_bytes: 2560