#include <fstream>

using namespace std;
ifstream f("hamilton.in");
ofstream g("hamilton.out");
struct nod
{
    int val,cost;
    nod *urm;
};
typedef nod *pnod;
#define inf 1000000000
pnod v[20],p;
int n,m,minim=inf,be[20],act,exista[20];
void ad(int x,int y,int c)
{
    p=new nod;
    p->val=y;
    p->cost=c;
    p->urm=v[x]->urm;
    v[x]->urm=p;
}
void ciclu(int i,int nivel)
{
    if(nivel==n)
    {
        if(exista[i]!=0)
            minim=min(minim,act+exista[i]);
    }
    {be[i]=1;
    pnod p=v[i]->urm;
    while(p)
    {
        if(be[p->val]==0)
        {
            act+=p->cost;
            ciclu(p->val,nivel+1);
            act-=p->cost;
        }
        p=p->urm;
    }
    be[i]=0;}
}
int main()
{
    int i,x,y,c;
    f>>n>>m;
    for(i=0;i<n;i++)
    {
        v[i]=new nod;
        v[i]->urm=0;
    }
    for(i=1;i<=m;i++)
    {
        f>>x>>y>>c;
        ad(x,y,c);
        if(y==0)
            exista[x]=c;
    }
    ciclu(0,1);
    if(minim==inf)
        g<<"Nu exista solutie";
    else
        g<<minim;
    return 0;
}