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#include <fstream>
#include <vector>
#include <stack>
#include <algorithm>
#include <cstring>
using namespace std;
ifstream fin ("hamilton.in");
ofstream fout ("hamilton.out");
const int NMAX = 18;
const int MAX_CONF = (1 << NMAX);
const int INF = (1<<29);
int N; int M;
vector<int> G[NMAX];
int D[MAX_CONF][NMAX]; //costul minim de a ajunge de la nodul 0 ( ales de noi) pana la nodul NMAX, trecand prin toate nodurile i cu (1 << i) & MAX_CONF = 1
int min_sum = INF;
int C[NMAX][NMAX];
void read() {
fin >> N >> M;
for(int i = 1; i <= M; ++i) {
int x; int y; int cost;
fin >> x >> y >> cost;
G[y].push_back(x);
C[x][y] = cost;
}
}
int calc(int start, int conf, int last) {
if(D[conf][last] == -1) {
D[conf][last] = INF;
for(unsigned i = 0 ; i < G[last].size(); ++i)
if((1 << G[last][i]) & conf) {
if(start == G[last][i] && ( ( (1 << last) ^ conf) != (1 << start) ) ) continue ;//nu vreau sa trec de 2 ori pin nodul start,
//decat daca configuratia noastra consta doar din nodul de start si nodul last, practic astfel intializez
//configuratiile cudoar 2 noduri cu costul muchiei intre ele
D[conf][last] = min(D[conf][last], calc(start, conf ^ (1 << last), G[last][i] ) + C[ G[last][i] ][ last ] );
}
}
return D[conf][last];
}
void solve() {
int conf = (1 << N);
memset(D, -1, sizeof(D));
for(int i = 0 ; i < N; ++i)
D[(1 << i)][i] = 0; //costul minim de ajunge de la nodul i la el insusi, adica 0
for(unsigned j = 0; j < G[0].size(); ++j)
min_sum = min(min_sum, calc(0, conf - 1, G[0][j]) + C[ G[0][j] ][ 0 ]);
}
int main() {
read();
solve();
if(min_sum == INF)
fout << "Nu exista solutie";
else
fout << min_sum << '\n';
return 0;
}