It seems python has a low recursion Limit creating problems like runtime error. I have faced this problem in the following questions. It seems we have to use sys.setrecursionlimit().

667C - Reberland Linguistics without using sys.setrecursionlimit 18166330. passed 18165938.

but this is also not working in some cases

445A - DZY Loves Chessboard

(python3 runtimeerror with limit set)[submission:18166280]

 (python2 same code) [submission:18166286]

Can anyone shed some light over this topic

did anyone face similar problems with python and why python3 is failing and python2 is passing with eventhough i set recursionlimit explicilty.

Thanks