In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[9649, 'l', 6305, 'W', 't', 'B', 'f', 'w', '3793', '7755', 'Q', 'A', 'b', 'h', 'A', '7999', 's', 'c', 'S', 'W', 'c', 5747, 4835, 3585, 8755, 'S', 4397, 'q', 3999, 'e'], [1797, 471, 'I', 'W', 1659, 'f', 'w', '3793', '7755', 'Q', 'A', 'b', 'h', 'A', '7999', 's', 'c', 's', 'g', 'q', 3753]