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#include 
   
    #include 
    
     using namespace std;int n;int adj[20000];int parent[20000];int children[20000][20000];int f[20000][2];void add_edge(int u, int v) {    adj[u].push_back(v);    adj[v].push_back(u);}void dfs(int u, int p) {    parent[u] = p;    for (int v : adj[u]) {        if (v != p) {            children[u].push_back(v);            dfs(v, u);        }    }}int main() {    cin >> n;    adj.resize(n);    for (int i = 0; i < n; ++i) {        adj[i].clear();    }    for (int i = 0; i < n; ++i) {        int k, x1;        cin >> x1 >> k;        for (int j = 0; j < k; ++j) {            int y1;            cin >> y1;            add_edge(x1, y1);        }    }    parent[0] = -1;    children[0].clear();    dfs(0, -1);    for (int u = 0; u < n; ++u) {        f[u][0] = 0;        f[u][1] = 0;    }    stack
     
       stack;    stack.push(0);    bool visited[20000];    visited[0] = true;    while (!stack.empty()) {        int u = stack.top();        stack.pop();        vector
      
        child_indices;        for (size_t i = 0; i < children[u].size(); ++i) {            if (!visited[children[u][i]]) {                child_indices.push_back(i);            }        }        for (size_t i = 0; i < child_indices.size(); ++i) {            int v = children[u][child_indices[i]];            if (!visited[v]) {                visited[v] = true;                stack.push(v);            }        }        for (size_t i = 0; i < children[u].size(); ++i) {            int v = children[u][i];            if (!visited[v]) {                f[u][0] = f[v][1];                f[u][1] += f[v][0];            }        }    }    int result = min(f[0][0], f[0][1]);    cout << result << endl;}
      
     
    
   

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