[算法] 匈牙利算法 poj 1274 示例 [ 二分图匹配 入门篇 ] O(n*m) Hopcroft O(sqrt(n)*m)

#include <iostream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <cmath>
#include <vector>
#include <stack>
#include <deque>
#include <queue>
#include <bitset>
#include <list>
#include <map>
#include <set>
#include <iterator>
#include <algorithm>
#include <functional>
#include <utility>
#include <sstream>
#include <climits>
#include <cassert>
#define BUG puts("here!!!");

using namespace std;
const int N = 205;
vector<int> p
;
int mat
;
bool vis
;
int n, m;
int ca, e;
bool dfs(int u) {
for(int i = 0; i < p[u].size(); i++) {
int to = p[u][i];
if(!vis[to]) {
vis[to] = true;
if(mat[to] == 0 || dfs(mat[to])) {
mat[to] = u;
return true;
}
}
}
return false;
}
int Maxmatch() {
int num = 0;
memset(mat, 0, sizeof(mat));
for(int i = 1; i <= n; i++) {
memset(vis, 0, sizeof(vis));
if(dfs(i)) num++;
}
return num;
}
int main() {
while(scanf("%d%d", &n, &m) == 2) {
for(int i = 0; i <= n; i++) {
p[i].clear();
}
for(int i = 1; i <= n; i++) {
scanf("%d", &ca);
while(ca--) {
scanf("%d", &e);
p[i].push_back(e);
}
}
printf("%d\n", Maxmatch());
}
return 0;
}