#include <fstream>
#include <vector>
const int NMAX = 18;
const int INF = 100000000;
using namespace std;
ifstream fin ( "hamilton.in" );
ofstream fout ( "hamilton.out" );
int c[NMAX+5][NMAX+5];
int dp[(1<<NMAX)+5][NMAX+5];
vector <int> a[NMAX+5];
int n;
inline void init () {
    for ( int i = 0 ; i < n ; ++i )
        for ( int j = 0 ; j < n ; ++j )
            c[i][j] = INF;
}
int main() {
    int m, my_min, i, j, x, y, k;
    fin >> n >> m;
    init();
    for ( i = 1 ; i <= m ; ++i )  {
        fin >> x >> y;
        fin >> c[x][y];
        a[y].push_back ( x );
    }

    for ( i = 0 ; i < ( 1 << n ) ; ++ i )
        for ( j = 0 ; j < n ; ++ j )
            dp[i][j] = INF;
    dp[1][0] = 0;
    for ( i = 0 ; i < ( 1 << n ) ; ++ i )
        for ( j = 0 ; j < n ; ++ j )
            if ( i & ( 1 << j ) )
                for ( size_t k = 0 ; k < a[j].size() ; ++ k )
                    if ( i & ( 1 << a[j][k] ) )
                        dp[i][j] = min ( dp[i][j], dp[i^(1<<j)][a[j][k]] + c[a[j][k]][j] );
    my_min = INF;
    for ( size_t i = 0 ; i < a[0].size() ; ++ i )
        my_min = min ( my_min, dp[(1<<n)-1][a[0][i]] + c[a[0][i]][0] );
    if ( my_min == INF )
        fout << "Nu exista solutie";
    else
        fout << my_min;
    return 0;
}