Given two strings A (n characters) and B (m characters), find their longest common subsequence. (eg. The longest common sub sequence for abcabc and abcbcca is abcbc.)

There is a standard dynamic programming solution:
 
== code(c) |
best[i][j] = longest common sub sequence for A[0:i] and B[0:j], computed as below:
==

There is a standard dynamic programming solution which uses an array best[i][j] to mean the longest common sub sequence for A[0:i] and B[0:j], computed as below:

== code(c) |
if A[i] == B[j]: