Initial State

		A
		B	D
	C	E	F
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Goal State

		A
		B
		C	F
		D	E
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Operators:  
	Pick up a block (places block in robot hand)
	Put down a block (block must be in robot's hand)
	Stack a block onto another (block must be in robot's hand and destination clear)
	Unstack a block from another (places block in robot hand)

From initial state, possible moves:
	Pickup(C)
	Unstack(A)
	Unstack(D)

Pickup(C) has moves:
	Putdown(C)
	Stack(C, A)
	Stack(C, D)
Unstack(A) has moves:
	Putdown(A)
	Stack(A, C)
	Stack(A, B)
	Stack(A, D)
Unstack(D) has moves:
	Putdown(D)
	Stack(D, C)
	Stack(D, A)
	Stack(D, F)


From goal state, possible moves:
	Stack(F, E)
	Stack(A, B)
Stack(F, E) has possible moves:
	Pickup(F)
	Unstack(F, x)
Stack(A, B) has possible moves:
	Pickup(A)
	Unstack(A, x)