#define _USE_MATH_DEFINES
#include <cstdio>
#include <iostream>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <complex>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <limits>
#include <climits>
#include <cfloat>
#include <functional>
#include <iterator>
using namespace std;

int main()
{
    int n;
    cin >> n;
    vector<vector<int> > f(n, vector<int>(n));
    for(int i=0; i<n; ++i){
        for(int j=0; j<n; ++j){
            cin >> f[i][j];
        }
    }

    vector<int> dp(1<<n, -1);
    dp[0] = 0;
    for(int i=0; i<(1<<n)-1; ++i){
        if(dp[i] == -1)
            continue;

        bitset<32> bs(i);
        int j = 0;
        while(bs[j])
            ++ j;
        bs[j] = true;

        for(int k=j+1; k<n; ++k){
            if(bs[k])
                continue;
            bs[k] = true;
            dp[bs.to_ulong()] = max(dp[bs.to_ulong()], dp[i] + f[j][k]);
            bs[k] = false;
        }
    }
    cout << dp.back() << endl;

    return 0;
}