每日AC（不想理罗，代码有点乱，别介意哈）

#include <bits/stdc++.h>

using namespace std;

const int INF = INT_MAX / 2;

int main() {

int n, m;
while(cin >> n >> m)
{
vector<vector<pair<int, int>>> adj(n);
for (int i = 0; i < m; ++i) {
    int a, b, c;
    cin >> a >> b >> c;
    a--; b--;
    adj[a].emplace_back(b, c);
    adj[b].emplace_back(a, c);
}

int pow3[11] = {1};
for (int i = 1; i <= n; ++i) {
    pow3[i] = pow3[i - 1] * 3;
}

int total_states = pow3[n];
vector<vector<int>> dp(total_states, vector<int>(n, INF));
queue<pair<int, int>> q;

for (int u = 0; u < n; ++u) {
    int s = pow3[u];
    dp[s][u] = 0;
    q.emplace(s, u);
}

while (!q.empty()) {
    auto [s, u] = q.front();
    q.pop();

    for (auto [v, c] : adj[u]) {
        int k = (s / pow3[v]) % 3;
        if (k >= 2) continue;

        int new_s = s + pow3[v];
        int new_cost = dp[s][u] + c;

        if (new_cost < dp[new_s][v]) {
            dp[new_s][v] = new_cost;
            q.emplace(new_s, v);
        }
    }
}

int min_cost = INF;
for (int s = 0; s < total_states; ++s) {
    bool valid = true;
    for (int i = 0; i < n; ++i) {
        if ((s / pow3[i]) % 3 == 0) {
            valid = false;
            break;
        }
    }
    if (valid) {
        for (int u = 0; u < n; ++u) {
            if (dp[s][u] < min_cost) {
                min_cost = dp[s][u];
            }
        }
    }
}

if (min_cost == INF) {
    cout << -1 << endl;
} else {
    cout << min_cost << endl;
}
}
return 0;

}