#include <iostream>
#include <string>
#include <sstream>
#include <stack>
#include <algorithm>
#include <cmath>
#include <queue>
#include <bitset>
#include <iomanip>
#include <limits>
#include <chrono>
#include <random>
#include <array>
#include <unordered_map>
#include <functional>
#include <complex>
#include <numeric>
#include <cctype>
#include <map>
#include <set>
#include <cstdlib>
#include <bitset>
#include <tuple>
#include <assert.h>
#include <deque>
#include <utility>
#include <fstream>

using namespace std;
typedef long long ll;
using ull = unsigned long long;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
//template<typename T> T gcd(T a, T b) { a = abs(a), b = abs(b); while (b > 0) { tie(a, b) = make_pair(b, a % b); }return a; }
//mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());

constexpr long long INF = 1LL << 60;
constexpr int inf = 1000000007;
//constexpr long long mod = 1000000007LL;
constexpr long long  mod = 998244353;


int main()
{

	cin.tie(nullptr);
	ios::sync_with_stdio(false);

	int n; cin >> n;
	vector<vector<int>> f(n, vector<int>(n)); for (auto& v : f) for (auto& e : v) cin >> e;
	
	map<int, int> dp;
	int e = (1 << n) - 1;
	dp[0] = 0;
	while (!dp.empty()) {
		auto itr = dp.begin();
		int S = itr->first;
		int cost = itr->second;
		if (S == e) {
			cout << cost << "\n";
			return 0;
		}
		int s = -1;
		for (int i = 0; i < n; i++) {
			if (!(S >> i & 1)) {
				if (s == -1) s = i;
				else {
					int nS = S | (1 << i) | (1 << s);
					if (dp.count(nS)) chmax(dp[nS], cost + f[s][i]);
					else dp[nS] = cost + f[s][i];
				}
			}
		}
		dp.erase(dp.begin());
	}
}