bzoj-1191(二分图最大匹配)

#include<iostream>
#include<algorithm>
#include<cstring>
#define maxn 2005
using namespace std;
int n;
int m;
int x,y;
int e[maxn][maxn];
int visit[maxn];
int match[maxn];
int dfs(int u)
{
    for(int i=0;i<n;i++)
    {
        if(!visit[i]&&e[u][i])
        {
            visit[i]=1;
            if(match[i]==-1||dfs(match[i]))
            {
                match[i]=u;match[u]=i;
                return 1;
            }
        }
    }
    return 0;
}
int main()
{

    cin>>n>>m;
    memset(e,0,sizeof(e));
    memset(match,-1,sizeof(match));
    for(int i=n;i<n+m;i++)
    {
        cin>>x>>y;
        e[i][x]=e[x][i]=1;
        e[i][y]=e[y][i]=1;
    }
    int ans=0;
    for(int i=n;i<n+m;i++)
    {
        memset(visit,0,sizeof(visit));
        if(dfs(i))
            ans++;
        else
            break;
    }
    cout<<ans<<endl;
    return 0;
}