#include<cstdio>
#include<algorithm>
#include<cstring>

using namespace std;

const int N = 21,S = 1 << 21;
typedef long long LL;

int n,m;
LL dist[N][N];
LL f[S][N];

int main(){
    scanf("%d%d",&n,&m);
    while(m--){
        LL a,b,c;
        scanf("%lld%lld%lld",&a,&b,&c);
        dist[a][b] = dist[b][a] = c;
    }
    
    for(int i = 1; i < (1 << n); ++i){
    	for(int j = 1; j <= n; ++j){
    		if(!(i & (1 << (j - 1)))) continue;
    		for(int k = 1; k <= n; ++k){
    			if(i & (1 << (k - 1))) continue;
    			f[i | (1 << (k - 1))][k] = max(f[i | (1 << (k - 1))][k],f[i][j] + dist[j][k]);
			}
		}
	}
	
	LL ans = -1;
	for(int i = 1; i < (1 << n); ++i){
		for(int j = 1; j <= n; ++j){
			if(!(i & (1 << (j - 1)))) continue;
			ans = max(ans,f[i][j]);
		}
	}	
	printf("%lld",ans);
    
    return 0;
}