logu P2016 WA

 vector<vector<T>>(m, vector<T>(n)); }
template <class T, T init> inline auto vv(int m) { return vector<vector<T>>(m, vector<T>(m, init)); }
template <class T, T init> inline auto vv(int m, int n) { return vector<vector<T>>(m, vector<T>(n, init)); }

template <class T> using mpq = priority_queue<T, vector<T>, greater<T>>;

using ll = long long;
using pii = pair<int, int>;
using vl = vector<ll>;
using vi = vector<int>;

int n;
vi g[2048];

pii dfs(int u, int pa)
{
    int all = 0;
    int min_delta = INT_MAX / 2;
    for (auto v : g[u]) {
        if (v == pa)
            continue;
        auto [sw, swn] = dfs(v, u);
        all += min(sw, swn);
        min_delta = min(min_delta, sw - swn);
    }
    return {all + 1, all + (min_delta > 0 ? min_delta : 0)};
}

int main(int argc, char **argv)
{
    cin >> n;
    for (int i = 0; i < n; ++i) {
        int u, v, k;
        cin >> u >> k;
        for (int