In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[2499, 'r', 5695, 7917, 'x', 'R', 547, 6293, 'P', 'R', '3639', '8503', '6843', '437', '8541', 'J', 'o', '8367', 'y', 'j', '861', 'G', 4305], [2207, 'h', '3639', '8503', '6843', '437', '8541', 'J', 'o', '8367', 'y', 'j', '861', 'I', 1047, 3379, 'W', 'Z', 'z', 6791, 'C', 8111]