In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[4251, 3593, 'P', 3175, 4495, 437, '3647', '855', '3473', 'd', '7077', '341', '4251', '3413', 'D', '3621', 'i', 'o', '7093', '8333', '4301', '8053', 'r', 'K', 'W', 'U', 'o', 4791, 'r', 'l', 't', 1871], [4863, 9509, 8363, 'i', 'w', 105, 'e', 'l', 'i', 843, 1233, 'a', 1595, '3647', '855', '3473', 'd', '7077', '341', '4251', '3413', 'D', '3621', 'i', 'o', '7093', '8333', '4301', '8053', 'Q', 'y', 'x', 4359, 'i', 215, 's', 5889, 9563, 'P', 189, 'q', 9877, 3997]