#include <bits/stdc++.h>
#define INF 2147483647
#define INF_LL 9223372036854775807
#define MOD 1000000007
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;

vector<vector<int> > mat;
int N, M;

int main() {
	cin >> N >> M;
	mat = vector<vector<int> >(N, vector<int>(N, -1));
	for (int i = 0; i < M; i++) {
		int a, b, c;
		cin >> a >> b >> c;
		a--; b--;
		mat[a][b] = mat[b][a] = c;
	}
	int ans = -1;

	vector<vector<int> > dp((1 << N), vector<int>(N, -1)); //dp[S][i] 集合Sに訪れていて駅iにいる
	for (int i = 0; i < N; i++)dp[1 << i][i] = 0;
	for (int i = 0; i < (1 << N); i++) {
		for (int j = 0; j < N; j++) {
			if (dp[i][j] == -1)continue;
			bool flag = false;
			for (int k = 0; k < N; k++) {
				if (i & (1 << k) || mat[j][k] == -1)continue;
				flag = true;
				dp[i + (1 << k)][k] = max(dp[i + (1 << k)][k], dp[i][j] + mat[j][k]);
			}
			if (!flag)ans = max(dp[i][j], ans);
		}

	}
	cout << ans << endl;
}