2054-Two-Best-Non-Overlapping-Events.java

class Solution {
    public int smallestChair(int[][] times, int targetFriend) {
        int target = times[targetFriend][0];
        Arrays.sort(times, (a, b) -> a[0] - b[0]);

        PriorityQueue<Integer> pq = new PriorityQueue<>();
        for (int i = 0; i < times.length; i++) {
            pq.offer(i);
        }

        PriorityQueue<int[]> pq_ = new PriorityQueue<>((a, b) -> a[0] - b[0]);
        for (int i = 0; i < times.length; i++) {
            while (!pq_.isEmpty() && pq_.peek()[0] <= times[i][0]) {
                pq.offer(pq_.poll()[1]);
            }

            if (times[i][0] == target) {
                break;
            }
            pq_.offer(new int[] { times[i][1], pq.poll() });
        }
        return pq.peek();
    }
}