updated by francis
Merge branch 'master' of https://github.com/fteng328/DNA-alignment
Revert "edit distance started"

This reverts commit 9f20d7cd08d42a33b87cddb93eb0c9e0b0b41f36.
Revert "Revert "edit distance started""

This reverts commit 443c02adfe928b5d6a1dd33fe2fdedc91d17f67a.
jaj