Global Sequence Alignment
The LCS problemcorresponds to a rather restrictive scoring that awards 1 for
matches and does not penalize indels. To generalize scoring,we extend the k-
letter alphabet A to include the gap character “−”, and consider an arbitrary
(k+1)×(k+1) scoring matrix , where k is typically 4 or 20 depending on the
type of sequences (DNA or protein) one is analyzing.