In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[8769, 't', 'k', 'N', 'E', '6461', '5993', 'E', 'p', 4585, 'W'], [3187, 2991, 4641, 7357, 'N', 'E', '6461', '5993', 'E', 'N', 'u']