deletions | additions       diff --git a/Points_and_Planes_We_do__.md b/Points_and_Planes_We_do__.md  index 006bb7f..67f6e9f 100644  --- a/Points_and_Planes_We_do__.md  +++ b/Points_and_Planes_We_do__.md 
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## Heap  We populate the heap   ## Correctedness  The heap stores all of the intervals we are currently intersecting with our ray. Our heap structure is defined to maintain the order of these intervals along the ray. We can only see a point if it is not behind any intervals when we reach it with our ray.  We emit a point IFF it is in front of the root of our heap. Our heap structure is defined to maintain the order of intervals along the ray, with the front-most being placed at the root.