In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['x', 'j', 'Y', 6449, 6661, 'N', '4799', 'e', 'v', 'j', 'Q', '5909', '7843', 'H', '6617', '6733', '2243', 'Y', 'p', '993', '8415', '37', 'f', 'F', '791', 'v', 'g', '7991', '1979', 'M', '8305', '8661', 'Y', 'x', 9533, 'C', 1877], ['B', 9831, 5291, 'I', 'A', 'k', 4307, 'm', 8115, 1455, 'o', '4799', 'e', 'v', 'j', 'Q', '5909', '7843', 'H', '6617', '6733', '2243', 'Y', 'p', '993', '8415', '37', 'f', 'F', '791', 'v', 'g', '7991', '1979', 'M', '8305', '8661', 'Y', 'b', 7787, 7779]