In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[9889, 'I', 'f', 'y', '3773', '4483', 'Y', '2325', 'M', '247', '8091', 'H', '3787', '3845', 'i', 'L', 't', '6949', '6019', '5929', 'm', 2573, 839, 'a', 'S', 9999, 'H', 135, 1089], ['Y', 'a', 9301, 'l', 'v', 'f', 'y', '3773', '4483', 'Y', '2325', 'M', '247', '8091', 'H', '3787', '3845', 'i', 'L', 't', '6949', '6019', '5929', 'Q', 9865, 7343, 741, 863, 'I', 'M', 'u']