In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[399, 'J', 4615, 2155, 'r', 'R', 'N', '4575', 'Z', 'G', '6427', '6949', 's', 'n', 4035], ['W', 'm', 'E', 'G', 'v', 4121, 'D', 'j', 'R', 'N', '4575', 'Z', 'G', '6427', '6949', 's', 'r', 'w', 'n', 6439, 8535, 'R']