Attempt Number: 4
Error Message: The action and resulting child state have already been explored.

Action Reasoning:
The last action taken was "paint-up(robot1, tile_0-1, tile_1-1, white)", which painted tile_0-1 white. According to the provided strategy, after painting up, we should move the robot horizontally if there are any unpainted tiles in the row above. Since tile_0-2 is unpainted, we should move robot1 to tile_1-2 using the "right" action. This action is valid and will bring us closer to painting tile_0-2.

New State Description:
Robot1 moves from tile_1-1 to tile_1-2. Tile_1-1 becomes clear, and tile_1-2 is now occupied by robot1. Robot1 is still holding the white paint gun.

Action Chosen:
right(robot1, tile_1-1, tile_1-2)
