Rectangles Covering

Question

I have N rectangles with sides parallel to the x- and y-axes. There is another rectangle, model. I need to create an algorithm that can tell whether the

Answer 1

There is a trivial O(N^2) approach that is similar to the "raster" approach that is brought up. Since all the rectangles are axis-parallel, there can only be at most 2N distinct x and y dimension. Sort all the x's and y's and remap: x_i -> i. So now you have a 2N x 2N matrix where you can easily use the naive O(N^2) algorithm.