simple_blocks.txt

Initial state: At(Tower1), BlockAt(A, Tower1), BlockAt(D, Tower1), On(D, A), OnBottom(A), OnTop(D), BlockAt(B, Tower2), BlockAt(C, Tower2), On(B, C), OnBottom(C), OnTop(B), Empty(Tower3)
Goal state:     On(A, B), On(B, C), OnTop(A), OnBottom(C)

Actions:
        Go(From, To)
        Preconditions: At(From), !At(To)
        Postconditions: At(To), !At(From)

        PlaceOn(Block1, Block2, Tower)
        Preconditions: At(Tower), Holding(Block1), BlockAt(Block2, Tower), OnTop(Block2)
        Postconditions: !Holding(Block1), !OnTop(Block2), BlockAt(Block1, Tower), OnTop(Block1), On(Block1, Block2)

        PlaceOnEmpty(Block1, Tower)
        Preconditions: At(Tower), Holding(Block1), Empty(Tower)
        Postconditions: !Holding(Block1), OnTop(Block1), BlockAt(Block1, Tower), OnBottom(Block1), !Empty(Tower)

        PickUp(Block1, Block2, Tower)
        Preconditions: At(Tower), OnTop(Block1), BlockAt(Block1, Tower), BlockAt(Block2, Tower), On(Block1, Block2)
        Postconditions: Holding(Block1), !OnTop(Block1), !BlockAt(Block1, Tower), !On(Block1, Block2), OnTop(Block2)

        PickUpLast(Block1, Tower)
        Preconditions: At(Tower), BlockAt(Block1, Tower), OnTop(Block1), OnBottom(Block1)
        Postconditions: Holding(Block1), !BlockAt(Block1, Tower), !OnTop(Block1), !OnBottom(Block1), Empty(Tower)