in reply to Longest Common Subsequence Question
Your method would fail for
S1 = aabbb S2 = aabbb S3 = aa
The answer is "aa", but your method will try to find the LCS("bbb", "aa") and will fail to find a result.
Update: Oops, I meant
S1 = aa1bbb S2 = aa2bbb S3 = aa