Current State ID: 31
Current State Description: Block 'c' is now on top of block 'b', making block 'b' no longer clear. Block 'a' remains on top of block 'd', and block 'd' is supporting block 'a'. The hand is now empty.

Child State ID: 43
Action Taken: unstack(a, d)
State Description: Block 'a' is now held in the hand, block 'd' is clear and on the table, block 'c' is on top of block 'b', and block 'b' is supporting block 'c'. The hand is no longer empty.

Child State ID: 44
Action Taken: unstack(c, b)
State Description: Block 'c' is now held in the hand. Block 'b' is clear and on the table. Block 'a' remains on top of block 'd', and block 'd' is supporting block 'a'. The hand is no longer empty.

