poj3041 Asteroids 二分匹配匈牙利模版题目

#include<iostream>
#include<cstdio>
#include<list>
#include<algorithm>
#include<cstring>
#include<string>
#include<queue>
#include<stack>
#include<map>
#include<vector>
#include<cmath>
#include<memory.h>
#include<set>

#define ll long long
#define LL __int64
#define eps 1e-8
const ll INF=9999999999999;

using namespace std;

#define M 400000100

#define inf 0xfffffff

int mp[512][512];
int marry[2512];
bool vis[2512];

int n,k;

void clear()
{
memset(mp,0,sizeof(mp));
memset(marry,-1,sizeof(marry));
}

bool dfs(int x)
{
for(int i=1;i<=n;i++)
{
if(mp[x][i] && !vis[i])
{
vis[i]=1;
if(marry[i]==-1 || dfs(marry[i]))
{
marry[i]=x;
return 1;
}
}
}
return 0;
}

int main(void)
{
while(scanf("%d %d",&n,&k)==2)
{
clear();
int u,v;
for(int i=0;i<k;i++)
{
scanf("%d %d",&u,&v);
mp[u][v]=1;
}
int ans=0;
for(int i=1;i<=n;i++)
{
memset(vis,0,sizeof(vis));
if(dfs(i))
ans++;
}
printf("%d\n",ans);
}
}