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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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