#include <iostream>
#include <fstream>
#include <vector>
#include <cstring>
using namespace std;
#define NMAX 19
#define MAXX 262200
#define INF 10000000
int n,m,x,y,co,viz[NMAX],sol = INF;
vector<int> a[NMAX];
int cost[NMAX][NMAX],C[MAXX][NMAX];

int calcul(int start, int config, int last)
{
    if(C[config][last]==-1)
    {
        C[config][last] = INF;

        for(int i=0;i<a[last].size();i++)
        {
            if(config & (1<<a[last][i]))
            {
                if(a[last][i] == start && ((config^(1<<last))!=(1<<start))) continue;
                C[config][last] = min(C[config][last],calcul(start,config ^ (1<<last),a[last][i])+cost[a[last][i]][last]);
            }
        }
    }

    return C[config][last];
}

int main()
{
    ifstream in("hamilton.in");
    ofstream out("hamilton.out");
    in >> n >> m;
    for(int i=0;i<n;i++)
        for(int j=0;j<n;j++)
            cost[i][j] = INF;
    for(int i=0;i<m;i++)
    {
        in >> x >> y >> co;
        a[y].push_back(x);
        cost[x][y] = co;
    }

    for(int i=0;i<n;i++)
    {
        memset(C,-1,sizeof(C));

        C[1<<i][i]=0;
        for(int j=0;j<a[i].size();j++)
        {

            sol = min(sol, calcul(i,(1<<n)-1,a[i][j])+cost[a[i][j]][i]);
        }
    }

    if(sol==INF)
        out << "Nu exista solutie";
    else
        out << sol;
    return 0;
}