Current State ID: 11
Current State Description: Block a is on top of block c. Block b is on the table and clear. Block d is on the table and clear. Block c is no longer clear. The hand is empty.

Child State ID: 16
Action Taken: unstack(a, c)
State Description: Block a is now held in the hand. Block c is clear and on the table. Block b is on the table and clear. Block d is on the table and clear. The hand is holding block a.

