Given a string, s, determine the maximum number of unique substringsA substring is defined as a continuous sequence of characters within a string. into which s can be split. You can divide s into any sequence of nonempty substrings, ensuring their concatenation reconstructs the original string. However, each substring in the split must be distinct.

Constraints:

• $1 \leq$ s.length $\leq 16$

• s contains only lowercase English letters.