3607. 电网维护

3607. 电网维护

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题目链接：3607. 电网维护

代码如下：

class Solution {
public:vector<int> processQueries(int c, vector<vector<int>>& connections, vector<vector<int>>& queries) {vector<vector<int>> g(c + 1);for (auto& e : connections) {int x = e[0], y = e[1];g[x].push_back(y);g[y].push_back(x);}vector<int> belong(c + 1, -1);//记录每个节点所属的连通块vector<priority_queue<int, vector<int>, greater<>>> heaps;priority_queue<int, vector<int>, greater<>> pq;auto dfs = [&](auto&& dfs, int x)->void {belong[x] = heaps.size();//记录节点x在哪个堆pq.push(x);for (int y : g[x]) {if (belong[y] < 0) {dfs(dfs,y);}}};for (int i = 1;i <= c;i++) {if (belong[i] < 0) {dfs(dfs, i);heaps.push_back(move(pq));}}vector<int> res;vector<int8_t> offline(c + 1);for (auto& q : queries) {int x = q[1];if (q[0] == 2) {offline[x] = true;continue;}if(!offline[x]) {res.push_back(x);continue;}auto& h = heaps[belong[x]];//懒删除：取堆顶的时候，如果离线，才删除while(!h.empty()&&offline[h.top()]) {h.pop();}res.push_back(h.empty() ? -1 : h.top());}return res;}
};