/* 
 * File:   main.cpp
 * Author: virtualdemon
 *
 * Created on May 16, 2010, 2:09 PM
 */
#include <vector>
#include <cstdlib>
#include <fstream>
#include <iterator>
#define Nmax 20
#define oo 2147483647

/*
 * 
 */
using namespace std;
typedef pair< int, int > pr;
int N, Mcost=oo;
bool was[Nmax];
int cycle[Nmax];
int C[Nmax][Nmax];
vector< int > G[Nmax];
inline void DFS( int x, int cost, int k )
{
    if( N == k )
    {
        if( C[cycle[N-1]][1] && Mcost > cost+C[cycle[N-1]][1] )
            Mcost=cost+C[cycle[N-1]][1];
        return;
    }
    vector< int >::const_iterator it=G[x].begin(), iend=G[x].end();
    for( ; it < iend; ++it )
        if( !was[*it] && C[x][*it] )
        {
            cycle[k]=*it;
            was[*it]=true;
            DFS( *it, cost+C[x][*it], k+1  );
            was[*it]=false;
        }
}
int main( void )
{
    int M, x, y;
    ifstream in( "hamilton.in" );
    for( in>>N>>M; M; --M )
    {
        in>>x>>y;
        in>>C[x+1][y+1];
        G[x+1].push_back(y+1);
    }
    cycle[0]=1;
    was[1]=true;
    DFS( 1, 0, 1 );
    ofstream out( "hamilton.out" );
    if( oo == Mcost  )
        out<<"Nu exista solutie\n";
    else out<<Mcost<<'\n';
    return EXIT_SUCCESS;
}