731. My Calendar II

T: O(nlogn + n^2) = O(n^2), n times to call book()

S: O(n)

class MyCalendarTwo {

    TreeMap<Integer, Integer> map;
    public MyCalendarTwo() {
        map = new TreeMap<>();
    }
    
    public boolean book(int start, int end) {
        map.put(start, map.getOrDefault(start, 0)+1);
        map.put(end, map.getOrDefault(end, 0)-1);
        
        int max = 0;
        int count = 0;
        for (int value : map.values()) {
            count += value;
            max = Math.max(max, count);
            if (max > 2) {
                
                map.put(start, map.get(start)-1);
                map.put(end, map.get(end)+1);
                if (map.get(start) == 0) {
                    map.remove(start);
                }
                if (map.get(end) == 0) {
                    map.remove(end);
                }
                
                return false;
            }
        }

        return true;
    }
}

/**
 * Your MyCalendarTwo object will be instantiated and called as such:
 * MyCalendarTwo obj = new MyCalendarTwo();
 * boolean param_1 = obj.book(start,end);
 */