Current State ID: 10
Current State Description: Block `a` is on the table and clear. Block `b` is on the table and clear. Block `c` is in the hand and no longer on block `b`. Block `d` is on the table and clear. The hand is holding block `c`.

Child State ID: 15
Action Taken: put-down(c)
State Description: Block `a` is on the table and clear. Block `b` is on the table and clear. Block `c` is on the table and clear. Block `d` is on the table and clear. The hand is empty.

Child State ID: 16
Action Taken: stack(c, b)
State Description: Block `a` is on the table and clear. Block `b` is on the table and not clear, holding block `c`. Block `c` is on block `b` and clear. Block `d` is on the table and clear. The hand is empty.

