leetcode

2402.cpp (1230B)

 class Solution {
   public:
     int mostBooked(int n, vector<vector<int>> &meetings) const {
         sort(begin(meetings), end(meetings));
 
         typedef pair<long long, int> record;
         priority_queue<record, vector<record>, greater<>> engaged;
         priority_queue<int, vector<int>, greater<>> unused;
         vector<int> count(n);
 
         for (int i = 0; i < n; i++)
             unused.push(i);
 
         for (const auto meeting : meetings) {
             const int s = meeting[0], e = meeting[1];
 
             while (!engaged.empty() && engaged.top().first <= s) {
                 unused.push(engaged.top().second);
                 engaged.pop();
             }
 
             if (!unused.empty()) {
                 const int room = unused.top();
                 unused.pop();
 
                 count[room] += 1;
                 engaged.push({e, room});
             } else {
                 const auto [end, room] = engaged.top();
                 engaged.pop();
 
                 count[room] += 1;
                 engaged.push({end + e - s, room});
             }
         }
 
         int maxi = 0;
         for (int i = 1; i < n; i++) {
             if (count[i] > count[maxi]) maxi = i;
         }
 
         return maxi;
     }
 };