How to fix list index out of range

[longmen]

If 16 is supposed to be up that means your board is wrong and 16 up cannot be a wall.

Though your solution is inefficient I think it works. Any problems you have are probably errors setting up the board.

Hi, I figured out the issue. There is one more thing I hope you could advise me. With this input 15 12 8 6 q 11 it prints out

Action.UP 99.99999999999999
Action.UP 99.99999999999999
Action.DOWN 0.8899999999999998
Action.DOWN 0.8899999999999998

However, I want it to update from UP to RIGHT if it prints UP for the second time and print out LEFT at the fourth output if it shows up as DOWN. Its output should always print out as UP RIGHT DOWN LEFT. Could you please advise? Thanks for all your responses!