#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[8]={1,0,-1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

int main(){
    ll n;cin >> n;
    vvl f(n,vl(n));
    rep(i,n)rep(j,n)cin >> f[i][j];
    unordered_map<ll,ll> mp;
    queue<ll> que;
    que.push(0);
    mp[0]=0;
    while(!que.empty()){
        ll bit=que.front();que.pop();
        ll x=-1;
        per(i,n)if(!(bit&(1<<i)))x=i;
        if(x==-1)break;
        rep(i,n){
            if(bit&(1<<i))continue;
            if(i==x)continue;
            ll cit=bit;cit|=1<<x;cit|=1<<i;
            if(mp.count(cit))chmax(mp[cit],mp[bit]+f[x][i]);
            else {
                que.push(cit);
                mp[cit]=mp[bit]+f[x][i];
            }
        }
    }
    /*for(auto p:mp){
        cout << bitset<8>(p.fi) << " " << p.se <<endl;
    }*/
    cout << mp[(1<<n)-1] <<endl;
}