Remember the year 2008? There was a post with the same title.   
      
   At the time the hardest euler problem was 177, at level 80%.   
   I have solved several level 100% problems but this problem   
   evaded me, till now!   
      
   https://projecteuler.net/problem=177   
   Integer Angled Quadrilaterals.   
   Let be a convex quadrilateral, with diagonals. At each vertex the   
   diagonal makes an angle with each of the two sides, creating eight   
   corner angles that must be an integral measured in degrees.   
   Find the number of such quadrilaterals.   
   Not only must you find how to generate them, but I kept apparently   
   generating duplicates. At last I generated all of them, and removed   
   duplicates and succeeded.   
      
   Groetjes Albert   
   --   
   Don't praise the day before the evening. One swallow doesn't make spring.   
   You must not say "hey" before you have crossed the bridge. Don't sell the   
   hide of the bear until you shot it. Better one bird in the hand than ten in   
   the air. First gain is a cat purring.            - the Wise from Antrim -   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)