< Back 2250. Count Number of Rectangles Containing Each Point We're given a list of points defining the heighest point of a rectangle, starting from the origin, (0, 0). We're also given a list of points. We're asked to find the number of rectangles a particular point, point[j], is in. This problem is annoying because the trick is to notice that the maximum height is 100. From here, we just bin all the rectangles by their maximum height, with each bin containing the sorted lengths of the triangles in that bin. For each point, we process the bins from the point's height to the maximum height. For each bin, we binary search for the first rectangle length that is greater than or equal to the point's x-coordinate. With this index, we can find the number of rectangles that contain the point. We append the counts to the result list. After processing all points, we return the result list. The solution is as follows: from bisect import bisect_left class Solution: def countRectangles( self, rectangles: List[List[int]], points: List[List[int]] ) -> List[int]: max_h = 100 lengths = [[] for _ in range(max_h + 1)] for l, h in rectangles: lengths[h].append(l) for h in range(1, max_h + 1): lengths[h].sort() ans = [] for x, y in points: count = 0 for h in range(y, max_h + 1): if lengths[h]: i = bisect_left(lengths[h], x) count += len(lengths[h]) - i ans.append(count) return ans _ Time Complexity: O(r log(r) + p log(r)) - Where r is the number of rectangles and p is the number of points. _ Space Complexity: O(r) - We store the lengths of the rectangles in bins.