High Level PQ tree Algorithm
Input is U = {A1,A2,...,An}, and subsets S1, S2, ..., Sm of U.
Initialization:
- T = P node with children A1, A2, ... , An
Calculate m restrictions:
- for j = 1 to m do T := Restrict(T,Sj)
At the end of iteration k:
- PQ(T) = the set of ordering of U where each set S1, S2, ... , Sk are contiguous.