#include <cstdio>
#include <vector>
#include <iostream>
#include <cstring>
using namespace std;

const int nmx = 20;
const int maxx = (1 << 18) + 1;
const int inf = 0x3f3f3f3f;

int n, m, dp[maxx][nmx], cost[nmx][nmx];
vector <int> g[nmx];

int main(){
    freopen("hamilton.in", "r", stdin);
    freopen("hamilton.out", "w", stdout);
    memset(dp, inf, sizeof(dp));
    dp[1][0] = 0;
    memset(cost, inf, sizeof(cost));
    scanf("%d %d", &n, &m);
    for(; m; --m){
        int n1, n2;
        scanf("%d %d", &n1, &n2);
        g[n2].push_back(n1);
        scanf("%d", &cost[n1][n2]);
    }
    for(int i = 0; i < (1 << n); ++i)
        for(int j = 0; j < n; ++j)
            if(i & (1 << j))
                for(size_t s = 0; s < g[j].size(); ++s)
                    if(i & (1 << g[j][s]))
                        dp[i][j] = min(dp[i][j], dp[i ^ (1 << j)][g[j][s]] + cost[g[j][s]][j]);
    int sol = inf;
    for(size_t s = 0; s < g[0].size(); ++s)
        sol = min(sol, dp[(1<<n)-1][g[0][s]] + cost[g[0][s]][0]);
    if(sol == inf)
        printf("Nu exista solutie\n");
    else
        printf("%d\n", sol);
    return 0;
}