feat: 2402. Meeting Rooms III

Author: upupming

leetcode/残酷刷题/2402. Meeting Rooms III.cpp

@@ -0,0 +1,38 @@
+typedef pair<long long, int> PII;
+class Solution {
+public:
+    int mostBooked(int n, vector<vector<int>>& meetings) {
+        sort(meetings.begin(), meetings.end(), [](auto &m1, auto &m2){
+            return m1[0] < m2[0];
+        });
+        vector<int> cnt(n, 0);
+        // <结束时间, room id>
+        priority_queue<PII, vector<PII>, greater<PII>> pq;
+        set<int> free;
+        for (int i = 0; i < n; i++) free.insert(i);
+        for (auto meet : meetings) {
+            long long s = meet[0], e = meet[1];
+            while (pq.size() && pq.top().first <= s) {
+                free.insert(pq.top().second);
+                pq.pop();
+            }
+            // delay to the first time of pq top
+            if (!free.size()) {
+                auto t = pq.top().first;
+                // 这里不能把所有 t 时刻结束的都放入 free
+                free.insert(pq.top().second);
+                pq.pop();
+                e = e-s+t, s = t;
+            }
+            auto it = free.begin();
+            pq.push({e, *it});
+            cnt[*it]++;
+            free.erase(it);
+        }
+        int ans = 0;
+        for (int i = 1; i < n; i++) {
+            if (cnt[i] > cnt[ans]) ans = i;
+        }
+        return ans;
+    }
+};