In a newly planned city, where a city is located at each integral coordinate in a 2-dimensional plane, there are n Amazon retailers. The ith retailer residing in the city at the coordinate (xi, yi) can deliver to all the cities covered by the rectangle having the 4 corner points (0, 0), (xi, 0), (xi, yi), (0, yi). We say that a point (a, b) is covered by a rectangle if it lies inside the rectangle or on its boundaries. Note that no 2 retailers reside in the same city.
Given q requests of the form (a, b), determine the number of retailers who can deliver to the city at the coordinate (a, b).