Count the number of adjacent boxes

Question

Suppose I have a set of (X,Y) coordinates of 1000 boxes.

         (    x1,    y1)    (    x2,    y2)      Area

         (0.0000,0.0000)    (0.3412,0.4175)           


        

Answer 1

In the scenario you describe boxes share corners, so if you computed all of the box corners then you could see which ones were touching

// O(n)
foreach box b {
   // compute b's other 2 corners and save them
}

// 16 * O(n^2) = O(n^2) 
foreach box b {
   foreach box other {
      // match if any of b's corners match any of others points
   }
}

There is probably a much more efficient/elegant solution, this one is somewhat naive.