#include <bits/stdc++.h>
using namespace std;
#define mod (int)1000000007
#define MOD (int)10000000007
#define X 1001100011100001111ll
#define M 26388279066623ll
#define all(a) a.begin(),a.end()
#define for0(i, n) for (int i = 0; i < n; i++)
#define for0e(i, n) for (int i = 0; i <= n; i++)
#define for1(i, n) for (int i = 1; i <n; i++)
#define loop(i,a,b) for (int i = a; i < b; i++)
#define bloop(i,a,b) for (int i = a ; i>=b;i--)
#define tc(t) int t; cin >> t; while (t--)
#define ll long long
#define pb emplace_back
#define fio ios_base::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL)
#define in(x) scanf("%d", &x)
#define rr return 0
#define prec(n) fixed<<setprecision(n)
#define maxpq priority_queue<int>
#define minpq priority_queue<int, vector<int>, greater<int> >
#define inf (int)(1e18)
#define ini(a, i) memset(a, i, sizeof(a))
#define vi vector<int> 
#define F first
#define S second
#define pi pair<int, int>
#define ppi pair<pair<int,int> , int >
#define vii vector<pi>
const int MAXN = (int)((1e5) + 100);
int max(int a,int b){if(a>b) return a; else return b;}
int min(int a,int b){if(a<b) return a; else return b;} 
int gcd(int a,int b) { if (a == 0) return b; return gcd(b%a, a);}
int cbrt(int x){ int lo=1,hi=min(2000000ll,x);while(hi-lo>1){int mid=(lo+hi)/2;if(mid*mid*mid<x){lo=mid;}else hi=mid;}if(hi*hi*hi<=x) return hi;else return lo;} 
const int dx[4] = {-1, 1, 0, 0};
const int dy[4] = {0, 0, -1, 1};
const int N =  (int)(1e6+5); 
#define n_l '\n'
#define dbg(...) cout << "[" << #__VA_ARGS__ << "]: "; cout << to_string(__VA_ARGS__) << endl
template <typename T, size_t N> int SIZE(const T (&t)[N]){ return N; } template<typename T> int SIZE(const T &t){ return t.size(); } string to_string(const string s, int x1=0, int x2=1e9){ return '"' + ((x1 < s.size()) ? s.substr(x1, x2-x1+1) : "") + '"'; } string to_string(const char* s) { return to_string((string) s); } string to_string(const bool b) { return (b ? "true" : "false"); } string to_string(const char c){ return string({c}); } template<size_t N> string to_string(const bitset<N> &b, int x1=0, int x2=1e9){ string t = ""; for(int __iii__ = min(x1,SIZE(b)),  __jjj__ = min(x2, SIZE(b)-1); __iii__ <= __jjj__; ++__iii__){ t += b[__iii__] + '0'; } return '"' + t + '"'; } template <typename A, typename... C> string to_string(const A (&v), int x1=0, int x2=1e9, C... coords); int l_v_l_v_l = 0, t_a_b_s = 0; template <typename A, typename B> string to_string(const pair<A, B> &p) { l_v_l_v_l++; string res = "(" + to_string(p.first) + ", " + to_string(p.second) + ")"; l_v_l_v_l--; return res; } template <typename A, typename... C> string to_string(const A (&v), int x1, int x2, C... coords) { int rnk = rank<A>::value; string tab(t_a_b_s, ' '); string res = ""; bool first = true; if(l_v_l_v_l == 0) res += n_l; res += tab + "["; x1 = min(x1, SIZE(v)), x2 = min(x2, SIZE(v)); auto l = begin(v); advance(l, x1); auto r = l; advance(r, (x2-x1) + (x2 < SIZE(v))); for (auto e = l; e != r; e = next(e)) { if (!first) { res += ", "; } first = false; l_v_l_v_l++; if(e != l){ if(rnk > 1) { res += n_l; t_a_b_s = l_v_l_v_l; }; } else{ t_a_b_s = 0; } res += to_string(*e, coords...); l_v_l_v_l--; } res += "]"; if(l_v_l_v_l == 0) res += n_l; return res; } void dbgm(){;} template<typename Heads, typename... Tails> void dbgm(Heads H, Tails... T){ cout << to_string(H) << " | "; dbgm(T...); } 
#define dbgm(...) cout << "[" << #__VA_ARGS__ << "]: "; dbgm(__VA_ARGS__); cout << endl

// ========================================================
signed main(){
  #ifndef ONLINE_JUDGE
  //freopen("input.txt", "r", stdin);
  //freopen("output.txt", "w", stdout);
  #endif
  fio;
    int n;
    cin>>n;
    vector<vi> h(n,vector<int>(3));
    for0(i,n){
       for0(j,3){
           cin>>h[i][j];
       }
    }
    // vector<vi> dp(n,vector<int>(3,-inf));
    
    for1(i,n){
        for0(j,3){
            h[i][j] += max(h[i-1][(j+1)%3],h[i-1][(j+2)%3]);
        }
    }
    cout<<max({h[n-1][0],h[n-1][1],h[n-1][2]})<<endl;
  rr;
}



Measured memory_bytes: 8708