#include<bits/stdc++.h>
using namespace std;
#define ALL(x) begin(x),end(x)
#define rep(i,n) for(int i=0;i<(n);i++)
#define debug(v) cout<<#v<<":";for(auto x:v){cout<<x<<' ';}cout<<endl;
#define mod 1000000007
using ll=long long;
const int INF=1000000000;
const ll LINF=1001002003004005006ll;
int dx[]={1,0,-1,0},dy[]={0,1,0,-1};
// ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}
template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return true;}return false;}

struct IOSetup{
    IOSetup(){
        cin.tie(0);
        ios::sync_with_stdio(0);
        cout<<fixed<<setprecision(12);
    }
} iosetup;
 
template<typename T>
ostream &operator<<(ostream &os,const vector<T>&v){
    for(int i=0;i<(int)v.size();i++) os<<v[i]<<(i+1==(int)v.size()?"":" ");
    return os;
}
template<typename T>
istream &operator>>(istream &is,vector<T>&v){
    for(T &x:v)is>>x;
    return is;
}

ll dp[1<<24];

signed main(){
    int n;cin>>n;
    vector<vector<int>> f(n,vector<int>(n));
    rep(i,n)rep(j,n) cin>>f[i][j];

    rep(i,1<<24) dp[i]=-LINF;
    dp[0]=0;

    for(int bit=0;bit<(1<<24);bit++){
        int bits=__builtin_popcount(bit);
        if(bits%2 or bits==n) continue;

        int fs;
        rep(i,n)if(!(bit>>i&1)){
            fs=i;
            break;
        }

        int nxt=bit|(1<<fs);

        for(int j=fs+1;j<n;j++)if(!((nxt>>j)&1)) chmax(dp[nxt|(1<<j)],dp[bit]+f[fs][j]);
    }
    cout<<dp[(1<<n)-1]<<endl;
    return 0;
}