rodney 1. If the goal statement G is satisfied in the current state C. then return Head-plan 2. Either (A)Back-Chainer adds an operator to the Tail-Plan,or (B)Operator-Application moves an operator from Tail-Plan to Head-plan Decision point: Decide whether to apply an operator or to add an operator to the tail 3. Recursively call Prodigy on the resulting plan Operator-Application 1. Pick an operator op in Tail-Plan which is an applicable operator that is (A) here 1s no op erator in tail-Plan ordered before (B the preconditions of op are satisfied in the current state C. Decision point: Choose an applicable operator to apply 2. Move op to the end of Head-Plan and update the current state C. Table 1 Execution-simulating algorithm