2223 - Sum of Scores of Built Strings\.

Hard

You are building a string s of length n one character at a time, prepending each new character to the front of the string. The strings are labeled from 1 to n, where the string with length i is labeled <code>s_i</code>.

• For example, for s = "abaca", <code>s₁ == "a"</code>, <code>s₂ == "ca"</code>, <code>s₃ == "aca"</code>, etc.

The score of <code>s_i</code> is the length of the longest common prefix between <code>s_i</code> and <code>s_n</code> (Note that <code>s == s_n</code>).

Given the final string s, return the sum of the score of every <code>s_i</code>.

Example 1:

Input: s = "babab"

Output: 9

Explanation: For s₁ == "b", the longest common prefix is "b" which has a score of 1.

For s₂ == "ab", there is no common prefix so the score is 0.

For s₃ == "bab", the longest common prefix is "bab" which has a score of 3.

For s₄ == "abab", there is no common prefix so the score is 0.

For s₅ == "babab", the longest common prefix is "babab" which has a score of 5.

The sum of the scores is 1 + 0 + 3 + 0 + 5 = 9, so we return 9.

Example 2:

Input: s = "azbazbzaz"

Output: 14

Explanation:

For s₂ == "az", the longest common prefix is "az" which has a score of 2.

For s₆ == "azbzaz", the longest common prefix is "azb" which has a score of 3.

For s₉ == "azbazbzaz", the longest common prefix is "azbazbzaz" which has a score of 9.

For all other s_i, the score is 0.

The sum of the scores is 2 + 3 + 9 = 14, so we return 14.

Constraints:

• <code>1 <= s.length <= 10⁵</code>

• s consists of lowercase English letters.