bzoj1191: [HNOI2006]超级英雄Hero

#include<cstdio>
#include<algorithm>
#include<cstring>
using namespace std;
const int maxn = 2000 + 10;
const int maxm = 4000 + 10;

int n,m,e;
int v[maxn],next[maxm],h[maxn];
int p[maxn];
bool vis[maxn];

void add(int a,int b) {
    v[e] = b; next[e] = h[a]; h[a] = e++; 
}

bool find(int u) {
    if(vis[u]) return false;
    vis[u] = true;
    
    for(int i = h[u]; ~i; i = next[i]) 
        if(!p[v[i]] || find(p[v[i]])) {
            p[v[i]] = u;
            return true;
        }
    
    return false;
}

int main() {
    scanf("%d%d",&n,&m);
    memset(h,-1,sizeof(h));
    for(int i = 1,a,b; i <= m; i++) {
        scanf("%d%d",&a,&b);
        add(i,a);
        add(i,b);
    }
    int res;
    for(res = 1; res <= m; res++) {
        memset(vis,0,sizeof(vis));
        if(!find(res))
            break; 
    }
    printf("%d\n",res-1);
    return 0;
}