Count DNA Subsequence
Declare and implement a method called
countDNASubsequence. It should take two nullable
the first a strand of DNA to examine, and the second a sequence to look for. It should return as an
number of nonoverlapping times that the sequence appears in the strand.
Both the strand and the sequence will be entirely made up of only the characters 'A', 'T', 'G', and 'C',
corresponding to the DNA base pairs.
For example, given the DNA strand
AAAAAAAA and the sequence
AA you should return 4, not 7, since the
AA only appears 4 non-overlapping times in the strand.
null or empty you should return 0.