程序自动分析 (离散化并查集)

原题
需要离散化的并查集题,留作个笔记

#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> PII;
const int N = 1e5 + 10;
int n, cnt;
vector<PII>eqs;//可以相等的两个数
vector<PII>uneqs;//不可相等的两个数

unordered_map<int, int> H;
int p[N * 2];

int mapping(int x) {
    
    
	if (H.count(x))
		return H[x];
	return H[x] = cnt++;
}

int find(int x) {
    
    
	if (p[x] != x)
		p[x] = find(p[x]);
	return p[x];
}


void slove() {
    
    
	cin >> n;
	cnt = 0;
	H.clear();
	eqs.clear();
	uneqs.clear();
	for (int i = 0; i < n; i++) {
    
    
		int x, y, e;
		cin >> x >> y >> e;
		x = mapping(x), y = mapping  (y);
		if (e) {
    
     //如果是连接
			eqs.push_back({
    
    x, y});
		} else {
    
    
			uneqs.push_back({
    
    x, y});
		}
	}
	for (int i = 0; i < cnt; i++) {
    
    
		p[i] = i;
	}
	for (auto it : eqs)
		p[find(it.first)] = find(it.second);
	bool flag = true;
	for (auto it : uneqs) {
    
    
		if (find(it.first) == find(it.second)) {
    
    
			cout << "NO" << endl;
			return;
		}
	}
	cout << "YES" << endl;
}

int main() {
    
    
	int T;
	cin >> T;
	while (T--) {
    
    
		slove();
	}
}

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转载自blog.csdn.net/fdxgcw/article/details/119827256