CDOJ 1144 Big Brother 二分图匹配

二分图匹配

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <string>
#include <fstream>
#include <list>
#include <stack>
#include <queue>
#include <deque>
#include <algorithm>
#include <map>
#include <set>
#include <vector>
using namespace std;
#define maxn 202
#define maxm 202
bool graph[maxn][maxm];
bool vis[maxm], flag;
int match[maxn];
int N, M;
bool find(int x)
{
	int j;
	for (j = 0; j < M; j++)
	{
		if (graph[x][j] == true && vis[j] == false)
		{
			vis[j] = true;
			if (match[j] == -1 || find(match[j]))
			{
				match[j] = x;
				return true;
			}
		}
	}
	return false;
}
int main()
{
	//freopen("input.txt","r",stdin);
	//freopen("output.txt","w",stdout);
	//ios::sync_with_stdio(false);
	//cin.tie(0); cout.tie(0);
	//ifstream in;
	//in.open("input.txt", ios::in);
	scanf("%d%d", &N, &M);
	int t, s;
	for (int i = 0; i < N; ++i)
	{
		scanf("%d", &t);
		for (int j = 0; j < t; ++j)
		{
			scanf("%d", &s);
			--s;
			graph[i][s] = true;
		}
	}
	memset(match, -1, sizeof(int)*maxn);
	int ans = 0;
	for (int i = 0; i < N; ++i)
	{
		memset(vis, 0, sizeof(vis));
		if (find(i))
			++ans;
	}
	printf("%d\n", ans);
	//while (1);
	return 0;
}