In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[1997, 'K', 'C', 5715, '1451', 'v', 'V', 't', '187', '8043', 'n', 'T', 'q', '601', 'x', '7661', 'P', 'N', 'U', 'F', 'g', 663, 'p'], ['B', 6945, 'W', 7791, 'f', 'w', 'r', 'S', 5085, 7093, 'm', 'Y', 'f', 'z', 9781, '1451', 'v', 'V', 't', '187', '8043', 'n', 'T', 'q', '601', 'x', '7661', 'P', 'N', 'U', 'F', 'W', 'a', 3841, 'v']