O'Rourke has studied a problem that is related to this one (along many others that relate to Computational Geometry) and as a consequence, produced a very beautiful method to efficiently solve it. His method is described in the paper Uniqueness of orthogonal connect-the-dots and is also clearly illustrated at cs.mcgill.ca/~cs644/Godfried/2005/Fall/s... . Note that it says that the polygon shouldn't share vertices in order to apply this method, but this happens very often in the problem we are discussing here.
Thus, all we need to do is to eliminate vertices that are shared. Note that this still produces a polygon, and it is the polygon that is wanted as result. Also observe that the list of rectangles must not contain duplicates (I will assume that is the case, otherwise preprocess it to make the list unique).
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.