In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['Q', 'L', 'M', 'A', 'u', 'h', '6997', 'f', 2855, 6477], ['N', 'h', 'x', 'C', 'A', 'u', 'h', '6997', 'r', 'V', 'u']