HDU 5486 Difference of Clustering 图论

 #include<iostream>
#include<cstdio>
#include<map>
#include<vector>
#include<algorithm>
#include<cstring>
using namespace std;

const int maxn = 1e6 + 10;

int n,_max;
map<pair<int, int>, int> mp;
vector<int> G[maxn], G2[maxn];
int in[maxn], in2[maxn];

void init() {
	_max = -1;
	mp.clear();
	for (int i = 0; i <maxn; i++) G[i].clear(),G2[i].clear();
	memset(in, 0, sizeof(in));
	memset(in2, 0, sizeof(in2));
}

int main() {
	int tc,kase=0;
	scanf("%d", &tc);
	while (tc--) {
		scanf("%d", &n);
		init();
		for (int i = 0; i < n; i++) {
			int u, v;
			_max = max(_max, u);
			_max = max(_max, v);
			scanf("%d%d", &u, &v);
			if (!mp[make_pair(u, v)]) {
				mp[make_pair(u, v)]++;
				G[u].push_back(v);
				in[v]++;
				G2[v].push_back(u);
				in2[u]++;
			}
		}
		int ans1=0, ans2=0,ans3=0;
		for (int i = 0; i <= _max; i++) {
			int su = 1;
			for (int j = 0; j < G[i].size(); j++) {
				int v = G[i][j];
				if (in[v] > 1) { su = 0; break; }
			}
			if (su) {
				if (G[i].size() == 1) ans3++;
				else if(G[i].size()>1) ans2++;
			}
		}
		for (int i = 0; i <= _max; i++) {
			int su = 1;
			for (int j = 0; j < G2[i].size(); j++) {
				int v = G2[i][j];
				if (in2[v] > 1) { su = 0; break; }
			}
			if (su) {
				if (G2[i].size() == 1);
				else if(G2[i].size()>1) ans1++;
			}
		}
		printf("Case #%d: %d %d %d\n", ++kase, ans2,ans1, ans3);
	}
	return 0;
}