In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[9119, 'k', 'K', 'R', '6039', 'K', 'f', '7929', 'S', 7321], ['U', 'S', 'I', 'L', '6039', 'K', 'f', '7929', 'C', 'J']