Resource Profile/Scheduling
1. Suppose the plan has 1..N levels.
a) Divide it into 1..K and K..N (K < N). b) If CSP succeeds on 1..K, i) Add actions after level K to free allocated resources but record current status of objects. ii) Divide K..N into K..M and M..N such that objects are needed after M (K < M < N). iii) Insert steps to reinstate the status of objects after M. iv) Recursively call self with levels of the plan as K..M <inserted levels> M..N. c) Else recursively call self with levels 1..K.