POJ [P2289] Jamie's Contact Groups

二分+二分图多重匹配

辣鸡ACM式读入

对于这种奇葩的读入方法,还是老老实实的用scanf吧

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <algorithm>
#define RST(a) memset((a),0,sizeof((a)))
using namespace std;
int init(){
	int rv=0,fh=1;
	char c=getchar();
	while(c<'0'||c>'9'){
		if(c=='-') fh=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9'){
		rv=(rv<<1)+(rv<<3)+c-'0';
		c=getchar();
	}
	return rv*fh;
}
int n,m,g[1005][1005],match[1005][1005],lim,cnt[1005];
bool f[1005];
bool hungarian(int u){
	for(int i=1;i<=g[u][0];i++){
		int v=g[u][i];
		if(!f[v]){
			f[v]=1;
			if(cnt[v]<lim){
				match[v][++cnt[v]]=u;
				return 1;
			}
			for(int j=1;j<=cnt[v];j++){
				if(hungarian(match[v][j])){
					match[v][j]=u;
					return 1;
				}
			}
		}
	}
	return 0;
}
bool chk(){
	/*RST(match);*/RST(cnt);
	for(int i=1;i<=n;i++){
		RST(f);
		if(!hungarian(i)) return 0;
	}
	return 1;
}
int main(){
	while(1){
		n=init();m=init();
		if(!n&&!m) break;
		char s[20];RST(g);
		for(int i=1;i<=n;i++){
			scanf("%s",s);//cout<<s<<endl;
			while(1){
				int t;
				scanf("%d",&t);
				t++;
				g[i][++g[i][0]]=t;
				if(cin.peek()=='\n'||cin.peek()=='\r'||(cin.peek()>='A'&&cin.peek()<='Z')) break;
			}
		}
		int l=1,r=n;
		int ans=0;
		while(l<=r){
			lim=(l+r)>>1;
			if(chk()) ans=lim,r=lim-1;
			else l=lim+1;
		}
		cout<<ans<<endl;
	}
	return 0;
}