Let @ will be any polytope.
- The first item must be P, starting with point.
- If the last item is H, then this polytope must have 2 things, where is the rest of notation, and must be connected each other.
- If the last item is G, than this polytope must be all points are rounded.
- If the last item is S[X], then this polytope is the rest of notation, with X vertices connected to each vertices.
- S is short as S and C is short as S.