#include <bits/stdc++.h> using namespace std; typedef long long signed int LL; typedef long long unsigned int LU; #define incID(i, l, r) for(int i = (l) ; i < (r); i++) #define incII(i, l, r) for(int i = (l) ; i <= (r); i++) #define decID(i, l, r) for(int i = (r) - 1; i >= (l); i--) #define decII(i, l, r) for(int i = (r) ; i >= (l); i--) #define inc(i, n) incID(i, 0, n) #define inc1(i, n) incII(i, 1, n) #define dec(i, n) decID(i, 0, n) #define dec1(i, n) decII(i, 1, n) #define inII(v, l, r) ((l) <= (v) && (v) <= (r)) #define inID(v, l, r) ((l) <= (v) && (v) < (r)) #define PB push_back #define EB emplace_back #define MP make_pair #define FI first #define SE second #define UB upper_bound #define LB lower_bound #define PQ priority_queue #define ALL(v) v.begin(), v.end() #define RALL(v) v.rbegin(), v.rend() #define FOR(it, v) for(auto it = v.begin(); it != v.end(); ++it) #define RFOR(it, v) for(auto it = v.rbegin(); it != v.rend(); ++it) template<typename T> bool setmin(T & a, T b) { if(b < a) { a = b; return true; } else { return false; } } template<typename T> bool setmax(T & a, T b) { if(b > a) { a = b; return true; } else { return false; } } template<typename T> bool setmineq(T & a, T b) { if(b <= a) { a = b; return true; } else { return false; } } template<typename T> bool setmaxeq(T & a, T b) { if(b >= a) { a = b; return true; } else { return false; } } template<typename T> T gcd(T a, T b) { return (b == 0 ? a : gcd(b, a % b)); } template<typename T> T lcm(T a, T b) { return a / gcd(a, b) * b; } // ---- ---- int n, f[24][24]; int dp[1 << 24]; bool z[1 << 24]; int main() { cin >> n; inc(i, n) { inc(j, n) { cin >> f[i][j]; } } queue<int> q; q.push(0); z[0] = true; while(! q.empty()) { int i = q.front(); q.pop(); int j = n; inc(jj, n) { if(i & (1 << jj)) { continue; } j = jj; break; } incID(k, j + 1, n) { if(i & (1 << k)) { continue; } int l = i | (1 << j) | (1 << k); if(setmax(dp[l], dp[i] + f[j][k]) && ! z[l]) { q.push(l); z[l] = true; } } } cout << dp[(1 << n) - 1] << endl; return 0; }