#include <fstream>
#include <vector>

using namespace std;

ifstream in("hamilton.in");
ofstream out("hamilton.out");

const int NMAX = 19,
XMAX = (1 << 18),
INF = (1 << 30);

int N, M, NN, Cost[NMAX][NMAX], C[XMAX][NMAX];

vector < int > G[NMAX];

void citire() {
    int x, y, i, j;
    in >> N >> M;
    for (int i = 0; i < N; i++)
        for (int j = 0; j < N; j++)
            Cost[i][j] = INF;

    for (i = 1; i <= M; ++i) {
        in >> x >> y;
        G[y].push_back(x);
        in >> Cost[x][y];
    }
    NN = (1 << N) - 1;
}

void calcul() {
    int i, j;
    for (int i = 0; i <= NN; ++i)
        for (int j = 0; j <= N; ++j)
            C[i][j] = INF;

    C[1][0] = 0;
    for(i = 0; i <= NN; ++i)
        for(j = 0; j < N; j++)
            if(i & (1 << j))
                for (int& x : G[j]) {
                    if (i & (1 << x))
                        C[i][j] = min(C[i][j], C[i ^ (1 << j)][x] + Cost[x][j]);
                }
}

int main(){

    int Sol = INF;
    citire();
    calcul();
    for (int& nod : G[0]) {
        Sol = min(Sol, C[NN][nod] + Cost[nod][0]);
    }
    if (Sol == INF)
        out << "Nu exista solutie";
    else
        out << Sol;

    return 0;
}