Attempt Number: 2
Error Message: The action and resulting child state have already been explored.

Action Reasoning:
The robot is currently at tile_1-0 and holding the black paint gun. According to the goal state, tile_0-0 should be painted black. The robot is in the correct position to paint the tile directly above it, which is tile_0-0. The preconditions for the "paint-up" action are satisfied: the robot is holding a color (black), and the tile above (tile_0-0) is clear. Therefore, the best action is to paint tile_0-0 black, as it directly contributes to achieving the goal state.

New State Description:
Tile_0-0 is now painted black. Robot1 remains at tile_1-0, holding the black paint gun. Tile_1-0 is still occupied by the robot, and tile_1-1 is clear.

Action Chosen:
paint-up(robot1, tile_0-0, tile_1-0, black)
