#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define mt make_tuple
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
#define pb push_back
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    vector<vi> f(n, vi(n));
    rep(i, n)rep(j, n)cin >> f[i][j];

    vi dp(1 << n, -1);
    dp[0] = 0;
    rep(S, (1 << n) - 1) if (dp[S] != -1) {
        int k = 0;
        rep(i, n)if (!(S >> i & 1)) {
            k = i;
            break;
        }
        int nS = S | 1 << k;
        FOR(i, k + 1, n) if (!(S >> i & 1)) {
            smax(dp[nS | 1 << i], dp[S] + f[i][k]);
        }
    }
    cout << dp.back() << endl;
}