Given a string s
, return the number of distinct substrings of s
.
A substring of a string is obtained by deleting any number of characters (possibly zero) from the front of the string and any number (possibly zero) from the back of the string.
Example 1:
Input: s = "aabbaba"
Output: 21
Explanation: The set of distinct strings is
["a","b","aa","bb","ab","ba","aab","abb","bab","bba","aba","aabb",
"abba","bbab","baba","aabba","abbab","bbaba","aabbab","abbaba","aabbaba"]
Example 2:
Input: s = "abcdefg"
Output: 28
Constraints:
1 <= s.length <= 500
s
consists of lowercase English letters.
Follow up: Can you solve this problem in O(n)
time complexity?

