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

void DFS(int nod,int cost, int nivel)
{

    viz[nod] = 1;

    for(int i=0;i<a[nod].size();i++)
    {
        if(viz[a[nod][i]]==0)
        {
              DFS(a[nod][i],cost + c[nod][i],nivel+1);
        }
        if(nivel==n && a[nod][i]==0)
        {
            sol = min(sol,cost+c[nod][i]);
        }
    }
    viz[nod] = 0;
}



int main()
{
    ifstream in("hamilton.in");
    ofstream out("hamilton.out");
    in >> n >> m;
    for(int i=0;i<m;i++)
    {
        in >> x >> y >> co;
        a[x].push_back(y);
        c[x].push_back(co);
    }
    DFS(0,0,1);
    if(sol==10000000)
        out << "Nu exista solutie";
    else
        out << sol;
    return 0;
}