stablegradients/pie-gem5-pairs huggingface dataset:
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

#define print printf("==================\n")

#define ll long long

#define pi acos(-1.0)

#define eps 1e-16

#define max3(a,b,c) max(a,max(b,c))

const ll INF = 1 << 30;

typedef pair<ll, ll  > payar;

typedef struct

{

    ll  x, y;

} point;

priority_queue<payar, vector<payar>,  greater<payar> > pq; ///accending

vector< pair<ll,payar  > > vpp;

vector < payar >  vp;



ll n ;

int ara[100005][4];

ll dp[100005][4];

ll cal(int day, int itm)

{

    if(day>n)

    {

        return 0;

    }



    if(dp[day][itm]!=-1)

        return dp[day][itm];

    ll maxi = -1;

    if(day==1)

    {

   return   maxi = dp[day][itm]=max3( cal(day+1,1)+ara[day][1], cal(day+1,2)+ara[day][2], cal(day+1,3)+ara[day][3] );



    }

    for(int i = 1 ; i<=3 ; i++)

    {

            if(i==itm)

                continue;

            maxi=max( cal(day+1,i)+ara[day][i],maxi);





    }

    return dp[day][itm]=maxi;

}



int main()

{



    cin>>n;

    memset(dp,-1,sizeof dp);

    for(int i =  1 ; i<=n ; i++)

    {

        for(int j  = 1 ; j<= 3 ; j++)

        {

            cin>>ara[i][j];

        }

    }

    cout<<cal(1,1);







    return  0 ;

}


// Faster C++ solution for the same problem (measured speedup: 4.217944643095166x):
#include <bits/stdc++.h>

#include <iostream>

using namespace std;



int main() {

  long long n;



  cin>>n;



  long long A[n],B[n],C[n];

  long long agendaDP[n][3];



  for(int i = 0; i < 3; i++){

    agendaDP[0][i] = 0;

  }



  for(int i = 0; i < n; i++){

      cin>>A[i]>>B[i]>>C[i];

  }



  for(int i = 0; i < n; i++){

      agendaDP[i+1][0] = max(agendaDP[i][1], agendaDP[i][2]) + A[i];

      agendaDP[i+1][1] = max(agendaDP[i][0], agendaDP[i][2]) + B[i];

      agendaDP[i+1][2] = max(agendaDP[i][0], agendaDP[i][1]) + C[i];

  }



  cout << max(agendaDP[n][0], max(agendaDP[n][1], agendaDP[n][2]))<<endl;



}
// Slower C++ solution:
#include <cstdio>

#include <cstdint>

#include <cinttypes>

#include <cstring>

#include <algorithm>



using i32 = std::int_fast32_t;



const int MaxN = 100001;



int A[MaxN][3], dp[MaxN][3];



signed main(signed argc, char **argv) {

	i32 n;

	std::scanf("%" SCNdFAST32, &n);

	

	for (i32 i = 0; i < n; ++ i) {

		std::scanf("%" SCNdFAST32 "%" SCNdFAST32 "%" SCNdFAST32, A[i], A[i] + 1, A[i] + 2);

	}

	

	memset(dp, 0, sizeof dp);

	

	dp[0][0] = A[0][0];

	dp[0][1] = A[0][1];

	dp[0][2] = A[0][2];

	

	for (i32 i = 1; i < n; ++ i) {

		for (i32 j = 0; j < 3; ++ j) {

			for (i32 a = 0; a < 3; ++ a) {

				if (a == j) {

					continue;

				}

				dp[i][j] = std::max(dp[i][j], dp[i - 1][a] + A[i][j]);

			}

		}

	}

	

	std::printf("%" PRIdFAST32, std::max(dp[n - 1][0], std::max(dp[n - 1][1], dp[n - 1][2])));

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.388315710730996x):
#include <bits/stdc++.h>

#include <iostream>

using namespace std;



int main() {

  long long n;



  cin>>n;



  long long A[n],B[n],C[n];

  long long agendaDP[n][3];



  for(int i = 0; i < 3; i++){

    agendaDP[0][i] = 0;

  }



  for(int i = 0; i < n; i++){

      cin>>A[i]>>B[i]>>C[i];

  }



  for(int i = 0; i < n; i++){

      agendaDP[i+1][0] = max(agendaDP[i][1], agendaDP[i][2]) + A[i];

      agendaDP[i+1][1] = max(agendaDP[i][0], agendaDP[i][2]) + B[i];

      agendaDP[i+1][2] = max(agendaDP[i][0], agendaDP[i][1]) + C[i];

  }



  cout << max(agendaDP[n][0], max(agendaDP[n][1], agendaDP[n][2]))<<endl;



}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

#define N (int)2e5

int n,a[N],b[N],c[N],memo[N][10];



// a = 0, b = 1, c = 2

int dp(int curr , int last) {

    if (curr > n) return 0;

    int &sol = memo[curr][last];

    if (sol != -1) return sol;

    if (last == 0) {

        sol = max(

            dp(curr + 1 , 1) + b[curr] ,

            dp(curr + 1 , 2) + c[curr]

        );

    } else if (last == 1) {

        sol = max(

            dp(curr + 1 , 0) + a[curr] ,

            dp(curr + 1 , 2) + c[curr]

        );

    } else {

        sol = max(

            dp(curr + 1 , 0) + a[curr] ,

            dp(curr + 1 , 1) + b[curr]

        );

    }

    return sol;

}



int main() {

    scanf("%d" , &n);

    for (int i = 1 ; i <= n ; i++)

        scanf("%d%d%d" , &a[i] , &b[i] , &c[i]);

    memset (memo , -1 , sizeof memo);

    printf("%d\n" , max(dp(2 , 0) + a[1] , max(dp(2 , 1) + b[1] , dp(2 , 2) + c[1])));

}


// Faster C++ solution for the same problem (measured speedup: 9.357427299594708x):
#include <bits/stdc++.h>

#include <iostream>

using namespace std;



int main() {

  long long n;



  cin>>n;



  long long A[n],B[n],C[n];

  long long agendaDP[n][3];



  for(int i = 0; i < 3; i++){

    agendaDP[0][i] = 0;

  }



  for(int i = 0; i < n; i++){

      cin>>A[i]>>B[i]>>C[i];

  }



  for(int i = 0; i < n; i++){

      agendaDP[i+1][0] = max(agendaDP[i][1], agendaDP[i][2]) + A[i];

      agendaDP[i+1][1] = max(agendaDP[i][0], agendaDP[i][2]) + B[i];

      agendaDP[i+1][2] = max(agendaDP[i][0], agendaDP[i][1]) + C[i];

  }



  cout << max(agendaDP[n][0], max(agendaDP[n][1], agendaDP[n][2]))<<endl;



}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

typedef long long LL;



int a[100005],b[100005],c[100005];

int dp[100007][5];



int Solve(int idx, int n, int prev){

	

	if(idx == n)return 0;

	

	if(dp[idx][prev] != -1)return dp[idx][prev];

	

	int ans = -1;

	for(int i = 1; i <= 3; i++){

		if(i == prev)continue;

		if(i == 1)ans = max(ans, a[idx] + Solve(idx+1, n, i));

		else if(i == 2)ans = max(ans, b[idx] + Solve(idx+1, n, i));

		else ans = max(ans, c[idx] + Solve(idx+1, n, i));		

	}

	return dp[idx][prev] = ans;

}



int main(){

	int n; cin>>n;

	memset(dp,-1,sizeof(dp));

	for(int i = 0; i < n; i++){

		cin>>a[i]>>b[i]>>c[i];

	}

	int ret = -1;

	for(int i = 1; i <= 3; i++){

		ret = max(ret, Solve(0,n,i));

	}

	cout<<ret<<endl;



//	cout<<Solve(0,n,0)<<endl;

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 3.004224077836645x):
#include <bits/stdc++.h>

#include <iostream>

using namespace std;



int main() {

  long long n;



  cin>>n;



  long long A[n],B[n],C[n];

  long long agendaDP[n][3];



  for(int i = 0; i < 3; i++){

    agendaDP[0][i] = 0;

  }



  for(int i = 0; i < n; i++){

      cin>>A[i]>>B[i]>>C[i];

  }



  for(int i = 0; i < n; i++){

      agendaDP[i+1][0] = max(agendaDP[i][1], agendaDP[i][2]) + A[i];

      agendaDP[i+1][1] = max(agendaDP[i][0], agendaDP[i][2]) + B[i];

      agendaDP[i+1][2] = max(agendaDP[i][0], agendaDP[i][1]) + C[i];

  }



  cout << max(agendaDP[n][0], max(agendaDP[n][1], agendaDP[n][2]))<<endl;



}
// Slower C++ solution:
#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <math.h>

#include <queue>

#include <stack>

#include <vector>

#include <algorithm>

#include <iostream>



using namespace std;



const int MAXN = 1e5 + 5;

int n,m;

int a,b,c;

int d,e,f;

vector <int> A;

vector <int> B;

vector <int> C;

vector <int> dp[MAXN];



int main()

{

	scanf("%d",&n);

	for(int i = 0; i < n; i++)

	{

		scanf(" %d %d %d",&a,&b,&c);

		A.push_back(a);//第一天的a现在是a[0]

		B.push_back(b);

		C.push_back(c);

	}

	dp[0].push_back(A[0]);

	dp[0].push_back(B[0]);

	dp[0].push_back(C[0]);

	for(int i = 1; i < n; i++)

	{

		d = max(dp[i - 1][1],dp[i - 1][2]);

		e = max(dp[i - 1][0],dp[i - 1][2]);

		f = max(dp[i - 1][0],dp[i - 1][1]);

		dp[i].push_back(d + A[i]);

		dp[i].push_back(e + B[i]);

		dp[i].push_back(f + C[i]);

		//dp[i][1] = max(dp[i - 1][2],dp[i - 1][3]) + a[i];

		//dp[i][2] = max(dp[i - 1][1],dp[i - 1][3]) + b[i];

		//dp[i][3] = max(dp[i - 1][1],dp[i - 1][2]) + c[i];

	}

	m = max(max(dp[n - 1][1],dp[n - 1][2]),dp[n - 1][0]);

	printf("%d\n",m);

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 3.518069236568268x):
#include <bits/stdc++.h>

#include <iostream>

using namespace std;



int main() {

  long long n;



  cin>>n;



  long long A[n],B[n],C[n];

  long long agendaDP[n][3];



  for(int i = 0; i < 3; i++){

    agendaDP[0][i] = 0;

  }



  for(int i = 0; i < n; i++){

      cin>>A[i]>>B[i]>>C[i];

  }



  for(int i = 0; i < n; i++){

      agendaDP[i+1][0] = max(agendaDP[i][1], agendaDP[i][2]) + A[i];

      agendaDP[i+1][1] = max(agendaDP[i][0], agendaDP[i][2]) + B[i];

      agendaDP[i+1][2] = max(agendaDP[i][0], agendaDP[i][1]) + C[i];

  }



  cout << max(agendaDP[n][0], max(agendaDP[n][1], agendaDP[n][2]))<<endl;



}
// Slower C++ solution:
#include<bits/stdc++.h>

using namespace std;

typedef long long int ll;

const int MAX=1e5+10;

int N,A[MAX],B[MAX],C[MAX],dp[MAX][3];

int solve(int idx,int pr)

{

    if(idx>N)return 0;

    if(dp[idx][pr]!=-1)return dp[idx][pr];

    int res=0;

    for(int i=1;i<=3;i++){

        if(i==pr)continue;

        int val=0;

        if(i==1)val=A[idx];

        if(i==2)val=B[idx];

        if(i==3)val=C[idx];

        res = max(res,solve(idx+1,i)+val);

    }

    return dp[idx][pr]=res;

}

int  main ()

{

    memset(dp,-1,sizeof dp);

    cin >> N;

    for(int i=1;i<=N;i++){

        cin >> A[i] >> B[i] >> C[i];

    }

    cout<<solve(1,0)<<endl;

    return 0;

}






// Faster C++ solution for the same problem (measured speedup: 2.1803930826753763x):
#include <bits/stdc++.h>

using namespace std;

#define f first

#define s second

#define ll long long

#define ld long double

#define pii pair <int,int>

#define pll pair <ll,ll>

#define pil pair <int,ll>

#define pli pair <ll,int>

#define ull unsigned long long

#define pdd pair <double,double>

#define pb push_back

#define mp make_pair

#define puu pair<ull,ull>

#define pvv pair<vector<int>, vector<int> >

#define _bp __builtin_popcount

#define ptt pair <Tree*,Tree*>

#define all(v) v.begin(),v.end();

const long double pi = acos(-1);

void boos()

{

     ios_base :: sync_with_stdio(false);

     cin.tie(0);

     cout.tie(0);

}

void file()

{

   freopen(".in","r",stdin);

   freopen(".out","w",stdout);

}

const ll INF = 1e9 + 7;

const ll INF1 = 998244353;

const ll LLINF = (ll)1e18;

const int  INTmx = (int)1e9;

const int N = 2e5 + 100;

ll dp[N][3];

ll a[N];

ll b[N];

ll c[N];

int main()

{

    //file();

    boos();

    int n;

    cin >> n;

    for(int i = 1;i <= n;i++)

    {

        cin >> a[i] >> b[i] >> c[i];

    }

    dp[1][0] = a[1];

    dp[1][1] = b[1];

    dp[1][2] = c[1];

    for(int i = 2;i <= n;i++)

    {

        dp[i][0] = max(dp[i - 1][1],dp[i - 1][2]) + a[i];

        dp[i][1] = max(dp[i - 1][0],dp[i - 1][2]) + b[i];

        dp[i][2] = max(dp[i - 1][0],dp[i - 1][1]) + c[i];

    }

    cout << max(dp[n][0],max(dp[n][1],dp[n][2]));

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

#define print printf("==================\n")

#define ll long long

#define pi acos(-1.0)

#define eps 1e-16

#define max3(a,b,c) max(a,max(b,c))

const ll INF = 1 << 30;

typedef pair<ll, ll  > payar;

typedef struct

{

    ll  x, y;

} point;

priority_queue<payar, vector<payar>,  greater<payar> > pq; ///accending

vector< pair<ll,payar  > > vpp;

vector < payar >  vp;



ll n ;

int ara[100005][4];

ll dp[100005][4];

ll cal(int day, int itm)

{

    if(day>n)

    {

        return 0;

    }



    if(dp[day][itm]!=-1)

        return dp[day][itm];

    ll maxi = -1;

    if(day==1)

    {

   return   maxi = dp[day][itm]=max3( cal(day+1,1)+ara[day][1], cal(day+1,2)+ara[day][2], cal(day+1,3)+ara[day][3] );



    }

    for(int i = 1 ; i<=3 ; i++)

    {

            if(i==itm)

                continue;

            maxi=max( cal(day+1,i)+ara[day][i],maxi);





    }

    return dp[day][itm]=maxi;

}



int main()

{



    cin>>n;

    memset(dp,-1,sizeof dp);

    for(int i =  1 ; i<=n ; i++)

    {

        for(int j  = 1 ; j<= 3 ; j++)

        {

            cin>>ara[i][j];

        }

    }

    cout<<cal(1,1);







    return  0 ;

}


// Faster C++ solution for the same problem (measured speedup: 4.163924587258836x):
#include <bits/stdc++.h>

using namespace std;

#define f first

#define s second

#define ll long long

#define ld long double

#define pii pair <int,int>

#define pll pair <ll,ll>

#define pil pair <int,ll>

#define pli pair <ll,int>

#define ull unsigned long long

#define pdd pair <double,double>

#define pb push_back

#define mp make_pair

#define puu pair<ull,ull>

#define pvv pair<vector<int>, vector<int> >

#define _bp __builtin_popcount

#define ptt pair <Tree*,Tree*>

#define all(v) v.begin(),v.end();

const long double pi = acos(-1);

void boos()

{

     ios_base :: sync_with_stdio(false);

     cin.tie(0);

     cout.tie(0);

}

void file()

{

   freopen(".in","r",stdin);

   freopen(".out","w",stdout);

}

const ll INF = 1e9 + 7;

const ll INF1 = 998244353;

const ll LLINF = (ll)1e18;

const int  INTmx = (int)1e9;

const int N = 2e5 + 100;

ll dp[N][3];

ll a[N];

ll b[N];

ll c[N];

int main()

{

    //file();

    boos();

    int n;

    cin >> n;

    for(int i = 1;i <= n;i++)

    {

        cin >> a[i] >> b[i] >> c[i];

    }

    dp[1][0] = a[1];

    dp[1][1] = b[1];

    dp[1][2] = c[1];

    for(int i = 2;i <= n;i++)

    {

        dp[i][0] = max(dp[i - 1][1],dp[i - 1][2]) + a[i];

        dp[i][1] = max(dp[i - 1][0],dp[i - 1][2]) + b[i];

        dp[i][2] = max(dp[i - 1][0],dp[i - 1][1]) + c[i];

    }

    cout << max(dp[n][0],max(dp[n][1],dp[n][2]));

}
// Slower C++ solution:
#include <cstdio>

#include <cstdint>

#include <cinttypes>

#include <cstring>

#include <algorithm>



using i32 = std::int_fast32_t;



const int MaxN = 100001;



int A[MaxN][3], dp[MaxN][3];



signed main(signed argc, char **argv) {

	i32 n;

	std::scanf("%" SCNdFAST32, &n);

	

	for (i32 i = 0; i < n; ++ i) {

		std::scanf("%" SCNdFAST32 "%" SCNdFAST32 "%" SCNdFAST32, A[i], A[i] + 1, A[i] + 2);

	}

	

	memset(dp, 0, sizeof dp);

	

	dp[0][0] = A[0][0];

	dp[0][1] = A[0][1];

	dp[0][2] = A[0][2];

	

	for (i32 i = 1; i < n; ++ i) {

		for (i32 j = 0; j < 3; ++ j) {

			for (i32 a = 0; a < 3; ++ a) {

				if (a == j) {

					continue;

				}

				dp[i][j] = std::max(dp[i][j], dp[i - 1][a] + A[i][j]);

			}

		}

	}

	

	std::printf("%" PRIdFAST32, std::max(dp[n - 1][0], std::max(dp[n - 1][1], dp[n - 1][2])));

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 1.3705352753393385x):
#include <bits/stdc++.h>

using namespace std;

#define f first

#define s second

#define ll long long

#define ld long double

#define pii pair <int,int>

#define pll pair <ll,ll>

#define pil pair <int,ll>

#define pli pair <ll,int>

#define ull unsigned long long

#define pdd pair <double,double>

#define pb push_back

#define mp make_pair

#define puu pair<ull,ull>

#define pvv pair<vector<int>, vector<int> >

#define _bp __builtin_popcount

#define ptt pair <Tree*,Tree*>

#define all(v) v.begin(),v.end();

const long double pi = acos(-1);

void boos()

{

     ios_base :: sync_with_stdio(false);

     cin.tie(0);

     cout.tie(0);

}

void file()

{

   freopen(".in","r",stdin);

   freopen(".out","w",stdout);

}

const ll INF = 1e9 + 7;

const ll INF1 = 998244353;

const ll LLINF = (ll)1e18;

const int  INTmx = (int)1e9;

const int N = 2e5 + 100;

ll dp[N][3];

ll a[N];

ll b[N];

ll c[N];

int main()

{

    //file();

    boos();

    int n;

    cin >> n;

    for(int i = 1;i <= n;i++)

    {

        cin >> a[i] >> b[i] >> c[i];

    }

    dp[1][0] = a[1];

    dp[1][1] = b[1];

    dp[1][2] = c[1];

    for(int i = 2;i <= n;i++)

    {

        dp[i][0] = max(dp[i - 1][1],dp[i - 1][2]) + a[i];

        dp[i][1] = max(dp[i - 1][0],dp[i - 1][2]) + b[i];

        dp[i][2] = max(dp[i - 1][0],dp[i - 1][1]) + c[i];

    }

    cout << max(dp[n][0],max(dp[n][1],dp[n][2]));

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

#define N (int)2e5

int n,a[N],b[N],c[N],memo[N][10];



// a = 0, b = 1, c = 2

int dp(int curr , int last) {

    if (curr > n) return 0;

    int &sol = memo[curr][last];

    if (sol != -1) return sol;

    if (last == 0) {

        sol = max(

            dp(curr + 1 , 1) + b[curr] ,

            dp(curr + 1 , 2) + c[curr]

        );

    } else if (last == 1) {

        sol = max(

            dp(curr + 1 , 0) + a[curr] ,

            dp(curr + 1 , 2) + c[curr]

        );

    } else {

        sol = max(

            dp(curr + 1 , 0) + a[curr] ,

            dp(curr + 1 , 1) + b[curr]

        );

    }

    return sol;

}



int main() {

    scanf("%d" , &n);

    for (int i = 1 ; i <= n ; i++)

        scanf("%d%d%d" , &a[i] , &b[i] , &c[i]);

    memset (memo , -1 , sizeof memo);

    printf("%d\n" , max(dp(2 , 0) + a[1] , max(dp(2 , 1) + b[1] , dp(2 , 2) + c[1])));

}


// Faster C++ solution for the same problem (measured speedup: 9.237584867324765x):
#include <bits/stdc++.h>

using namespace std;

#define f first

#define s second

#define ll long long

#define ld long double

#define pii pair <int,int>

#define pll pair <ll,ll>

#define pil pair <int,ll>

#define pli pair <ll,int>

#define ull unsigned long long

#define pdd pair <double,double>

#define pb push_back

#define mp make_pair

#define puu pair<ull,ull>

#define pvv pair<vector<int>, vector<int> >

#define _bp __builtin_popcount

#define ptt pair <Tree*,Tree*>

#define all(v) v.begin(),v.end();

const long double pi = acos(-1);

void boos()

{

     ios_base :: sync_with_stdio(false);

     cin.tie(0);

     cout.tie(0);

}

void file()

{

   freopen(".in","r",stdin);

   freopen(".out","w",stdout);

}

const ll INF = 1e9 + 7;

const ll INF1 = 998244353;

const ll LLINF = (ll)1e18;

const int  INTmx = (int)1e9;

const int N = 2e5 + 100;

ll dp[N][3];

ll a[N];

ll b[N];

ll c[N];

int main()

{

    //file();

    boos();

    int n;

    cin >> n;

    for(int i = 1;i <= n;i++)

    {

        cin >> a[i] >> b[i] >> c[i];

    }

    dp[1][0] = a[1];

    dp[1][1] = b[1];

    dp[1][2] = c[1];

    for(int i = 2;i <= n;i++)

    {

        dp[i][0] = max(dp[i - 1][1],dp[i - 1][2]) + a[i];

        dp[i][1] = max(dp[i - 1][0],dp[i - 1][2]) + b[i];

        dp[i][2] = max(dp[i - 1][0],dp[i - 1][1]) + c[i];

    }

    cout << max(dp[n][0],max(dp[n][1],dp[n][2]));

}
// Slower C++ solution:
#include <bits/stdc++.h>

using namespace std;

typedef long long LL;



int a[100005],b[100005],c[100005];

int dp[100007][5];



int Solve(int idx, int n, int prev){

	

	if(idx == n)return 0;

	

	if(dp[idx][prev] != -1)return dp[idx][prev];

	

	int ans = -1;

	for(int i = 1; i <= 3; i++){

		if(i == prev)continue;

		if(i == 1)ans = max(ans, a[idx] + Solve(idx+1, n, i));

		else if(i == 2)ans = max(ans, b[idx] + Solve(idx+1, n, i));

		else ans = max(ans, c[idx] + Solve(idx+1, n, i));		

	}

	return dp[idx][prev] = ans;

}



int main(){

	int n; cin>>n;

	memset(dp,-1,sizeof(dp));

	for(int i = 0; i < n; i++){

		cin>>a[i]>>b[i]>>c[i];

	}

	int ret = -1;

	for(int i = 1; i <= 3; i++){

		ret = max(ret, Solve(0,n,i));

	}

	cout<<ret<<endl;



//	cout<<Solve(0,n,0)<<endl;

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 2.9657483826434308x):
#include <bits/stdc++.h>

using namespace std;

#define f first

#define s second

#define ll long long

#define ld long double

#define pii pair <int,int>

#define pll pair <ll,ll>

#define pil pair <int,ll>

#define pli pair <ll,int>

#define ull unsigned long long

#define pdd pair <double,double>

#define pb push_back

#define mp make_pair

#define puu pair<ull,ull>

#define pvv pair<vector<int>, vector<int> >

#define _bp __builtin_popcount

#define ptt pair <Tree*,Tree*>

#define all(v) v.begin(),v.end();

const long double pi = acos(-1);

void boos()

{

     ios_base :: sync_with_stdio(false);

     cin.tie(0);

     cout.tie(0);

}

void file()

{

   freopen(".in","r",stdin);

   freopen(".out","w",stdout);

}

const ll INF = 1e9 + 7;

const ll INF1 = 998244353;

const ll LLINF = (ll)1e18;

const int  INTmx = (int)1e9;

const int N = 2e5 + 100;

ll dp[N][3];

ll a[N];

ll b[N];

ll c[N];

int main()

{

    //file();

    boos();

    int n;

    cin >> n;

    for(int i = 1;i <= n;i++)

    {

        cin >> a[i] >> b[i] >> c[i];

    }

    dp[1][0] = a[1];

    dp[1][1] = b[1];

    dp[1][2] = c[1];

    for(int i = 2;i <= n;i++)

    {

        dp[i][0] = max(dp[i - 1][1],dp[i - 1][2]) + a[i];

        dp[i][1] = max(dp[i - 1][0],dp[i - 1][2]) + b[i];

        dp[i][2] = max(dp[i - 1][0],dp[i - 1][1]) + c[i];

    }

    cout << max(dp[n][0],max(dp[n][1],dp[n][2]));

}
// Slower C++ solution:
#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <math.h>

#include <queue>

#include <stack>

#include <vector>

#include <algorithm>

#include <iostream>



using namespace std;



const int MAXN = 1e5 + 5;

int n,m;

int a,b,c;

int d,e,f;

vector <int> A;

vector <int> B;

vector <int> C;

vector <int> dp[MAXN];



int main()

{

	scanf("%d",&n);

	for(int i = 0; i < n; i++)

	{

		scanf(" %d %d %d",&a,&b,&c);

		A.push_back(a);//第一天的a现在是a[0]

		B.push_back(b);

		C.push_back(c);

	}

	dp[0].push_back(A[0]);

	dp[0].push_back(B[0]);

	dp[0].push_back(C[0]);

	for(int i = 1; i < n; i++)

	{

		d = max(dp[i - 1][1],dp[i - 1][2]);

		e = max(dp[i - 1][0],dp[i - 1][2]);

		f = max(dp[i - 1][0],dp[i - 1][1]);

		dp[i].push_back(d + A[i]);

		dp[i].push_back(e + B[i]);

		dp[i].push_back(f + C[i]);

		//dp[i][1] = max(dp[i - 1][2],dp[i - 1][3]) + a[i];

		//dp[i][2] = max(dp[i - 1][1],dp[i - 1][3]) + b[i];

		//dp[i][3] = max(dp[i - 1][1],dp[i - 1][2]) + c[i];

	}

	m = max(max(dp[n - 1][1],dp[n - 1][2]),dp[n - 1][0]);

	printf("%d\n",m);

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 3.4730126242424997x):
#include <bits/stdc++.h>

using namespace std;

#define f first

#define s second

#define ll long long

#define ld long double

#define pii pair <int,int>

#define pll pair <ll,ll>

#define pil pair <int,ll>

#define pli pair <ll,int>

#define ull unsigned long long

#define pdd pair <double,double>

#define pb push_back

#define mp make_pair

#define puu pair<ull,ull>

#define pvv pair<vector<int>, vector<int> >

#define _bp __builtin_popcount

#define ptt pair <Tree*,Tree*>

#define all(v) v.begin(),v.end();

const long double pi = acos(-1);

void boos()

{

     ios_base :: sync_with_stdio(false);

     cin.tie(0);

     cout.tie(0);

}

void file()

{

   freopen(".in","r",stdin);

   freopen(".out","w",stdout);

}

const ll INF = 1e9 + 7;

const ll INF1 = 998244353;

const ll LLINF = (ll)1e18;

const int  INTmx = (int)1e9;

const int N = 2e5 + 100;

ll dp[N][3];

ll a[N];

ll b[N];

ll c[N];

int main()

{

    //file();

    boos();

    int n;

    cin >> n;

    for(int i = 1;i <= n;i++)

    {

        cin >> a[i] >> b[i] >> c[i];

    }

    dp[1][0] = a[1];

    dp[1][1] = b[1];

    dp[1][2] = c[1];

    for(int i = 2;i <= n;i++)

    {

        dp[i][0] = max(dp[i - 1][1],dp[i - 1][2]) + a[i];

        dp[i][1] = max(dp[i - 1][0],dp[i - 1][2]) + b[i];

        dp[i][2] = max(dp[i - 1][0],dp[i - 1][1]) + c[i];

    }

    cout << max(dp[n][0],max(dp[n][1],dp[n][2]));

}