#include <fstream>
#include <vector>
#include <algorithm>

using namespace std;

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

vector <vector <int> > a, c;
unsigned long long x = -1, t = -1;

void read()
{
    int n, m;
    cin >> n >> m;
    a.resize(n);
    c.resize(n);
    for (int i = 0; i < n; i++)
    {
        c[i].resize(n);
        for (int j = 0; j < n; j++)
            c[i][j] = -1;
    }

    for (int i = 0, z, x, v; i < m; i++)
    {
        cin >> z >> x >> v;
        a[z].push_back(x);
        c[z][x] = v;
    }
}

void bk(vector <int> k, int y)
{
    if (k.size() == a.size())
    {
        long long q = c[k[k.size() - 1]][0];
        if (q == -1) return;
        q += y;
        if (q < x) x = q;
        return;
    }
    for (int i = 0; i < a[k[k.size() - 1]].size(); i++)
        if (count(k.begin(), k.end(), a[k[k.size() - 1]][i]) == 0)
        {
            k.push_back(a[k[k.size() - 1]][i]);
            y += c[k[k.size() - 2]][k[k.size() - 1]];
            bk(k, y);
            y -= c[k[k.size() - 2]][k[k.size() - 1]];
            k.pop_back();
        }
}

int main()
{
    read();

    vector <int> q(1);
    int s = 0;
    q[0] = 0;
    bk(q, s);

    if (x == t) cout << "Nu exista solutie";
    else cout << x;

    return 0;
}