#include<fstream>
#include<vector>
using namespace std;

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

const int Nmax=20;
const int oo=1<<29;
const int Maxx=1000000;

int n,m;
int mat[Nmax][Nmax];
int dp[Maxx][Nmax];
vector<int>v[Nmax];

inline void Citire()
{
    int i,j,x,y;
    fin>>n>>m;
    for (i=0;i<n;i++)
        for (j=0;j<n;j++)
            mat[i][j]=oo;
    for (i=1;i<=m;i++)
        {
            fin>>x>>y;
            v[y].push_back(x);
            fin>>mat[x][y];
        }
    for (i=0;i<(1<<n);i++)
        for (j=0;j<n;j++)
            dp[i][j]=-1;
}

inline int DpMemo(int conf,int nod)
{
    if (dp[conf][nod]==-1)
        {
            dp[conf][nod]=oo;
            for (vector<int>::iterator it=v[nod].begin();it!=v[nod].end();it++)
                if (conf&(1<<(*it)))
                    dp[conf][nod]=min(dp[conf][nod],DpMemo(conf-(1<<nod),*it)+mat[*it][nod]);
        }
    return dp[conf][nod];
}

inline void Solve()
{
    int i,minim=oo;
    dp[1][0]=0;
    for (i=1;i<n;i++)
        minim=min(minim,DpMemo((1<<n)-1,i)+mat[i][0]);
    if (minim!=oo)
        fout<<minim;
    else fout<<"Nu exista solutie";
    fout<<"\n";
}

int main()
{
    Citire();
    Solve();
    return 0;
}