In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[7845, 789, 'y', 'g', '3853', 'w', 'e', 'S', 107, 'B', 'W'], ['a', 'O', 'p', 8451, 'K', 'y', 'g', '3853', 'w', 'e', 'j', 'N']