a = [[2, 0, 0, 1, 0],
[0, 0, 0, 1, 0],
[0, 0, 0, 0, 0]]

['R3', 'D2', 'R1']

b = [[0, 2, 0, 0, 1],
[0, 0, 0, 0, 1],
[0, 0, 0, 0, 1],
[0, 0, 0, 0, 0]]

['R3', 'D3']

c = [[1, 0, 0, 0, 2],
[0, 0, 0, 0, 1],
[1, 0, 0, 0, 0],
[0, 0, 0, 0, 0]]

['L4', 'D1', 'R4', 'D1', 'L4', 'D1', 'R4']

br0! yours just fine, see my much more stupid solution you will be shocked as I did

Hi!

I just facing same problem as yours, and here is the reason and how you fix it:

The problem expected you return the int value instead of just print the value out. In this case, you need to convert Nontype datetype to integer datatype to pass the test.

Best regards,