Given a string s that consists only of the characters 'a', 'b', and 'c', return the number of substrings that contain at least one occurrence of each of the three characters.
Constraints:
s.length
s consists only of characters 'a', 'b', or 'c'.
Given a string s that consists only of the characters 'a', 'b', and 'c', return the number of substrings that contain at least one occurrence of each of the three characters.
Constraints:
s.length
s consists only of characters 'a', 'b', or 'c'.