Problem C

最大独立集

#include <iostream>
#include <cstdio>
#include <queue>
#include <cstring>
#include <string>
#include <cmath>
#include <vector>
#include <map>
#include <stack>
#include <algorithm>
//#include "myAlgorithm.h"

#define MAX 10005
#define OFFENCE (1e9 + 5)
#define INF (1e8 + 5)
#define eps 1e-9
#define Rep(s, e) for( int i = s; i <= e; i++)
#define Cep(e, s) for( int j = e; j >= s; j --)
#define PI acos(-1.0)
//#pragma comment(linker, "/STACK:36777216")
using namespace std;
int n;
int match[MAX],v[MAX];
vector<vector<int> >adj;
bool find(int node){
    int len = adj[node].size(), pos;
    Rep(0, len - 1){
        pos = adj[node][i];
        if(!v[pos]){
            v[pos] = 1;
            int pre = match[pos];
            if(pre == -1 || find(pre)){
                match[pos] = node;
                //match[node] = pos;
                return true;
            }
        }
    }
    return false;
}
int main() {
    while(cin>>n){
        adj.assign(n + 1, vector<int>() );
        memset(match, -1, sizeof(match));
        int c, a, s;
        Rep(0, n - 1){
            scanf("%d: (%d)", &s, &c);
            //cout<<c<<endl;
            for(int j = 0; j < c;j++){
                scanf("%d", &a);
                adj[s].push_back(a);
                //cout<<a<<endl;
            }
        }///end make adj;
        int ans = 0;
        for(int i = 0; i < n; i++){
            if(find(i))ans++;
            memset(v, 0, sizeof(v));
        }
        //cout<<ans<<endl;
        cout<<n - ans/2<<endl;
    }
    return 0;
}
/**

*/