In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[8515, 3071, 417, 6425, 7957, 'a', 'l', 'C', '2181', '617', '8139', 'U', 'C', 'I', 'E', 'Y', '177', '3447', 'r', '9929', '417', '9007', 'u', '7593', '3079', 'u', 3909, 'i', 'y', 9037, 'y', 4559, 885, 9773, 'j', 7313, 'C', 8689], ['j', 1755, 'K', 639, 9799, 8221, 'v', 'Q', 7851, 'I', 'c', 3873, 'v', 'W', 'n', '2181', '617', '8139', 'U', 'C', 'I', 'E', 'Y', '177', '3447', 'r', '9929', '417', '9007', 'u', '7593', '3079', 867, 'L', 'u', 'i', 'B', 'V', 'i']