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#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
using namespace std;

int main() {
    int n;
    scanf("%d", &n);
    
    long long w[3][3];
    for (int i = 0; i < 3; ++i) {
        for (int j = 0; j < 3; ++j) {
            scanf("%lld", &w[i][j]);
        }
    }
    
    vector<long long> dp(3, 0);
    vector<long long> ndp(3, 0);
    
    // 读取第一天的数值并初始化
    long long a, b, c;
    scanf("%lld %lld %lld", &a, &b, &c);
    dp[0] = a;
    dp[1] = b;
    dp[2] = c;
    
    for (int i = 1; i < n; ++i) {
        scanf("%lld %lld %lld", &a, &b, &c);
        ndp[0] = max(dp[1] + w[1][0], dp[2] + w[2][0]) + a;
        ndp[1] = max(dp[0] + w[0][1], dp[2] + w[2][1]) + b;
        ndp[2] = max(dp[0] + w[0][2], dp[1] + w[1][2]) + c;
        dp.swap(ndp);
    }
    
    long long ans = max({dp[0], dp[1], dp[2]});
    printf("%lld\n", ans);
    
    return 0;
}