{leetcode}/problems/number-of-good-ways-to-split-a-string/[LeetCode - 1525. Number of Good Ways to Split a String ^]
You are given a string s.
A split is called good if you can split s into two non-empty strings s<sub>left</sub> and s<sub>right</sub> where their concatenation is equal to s (i.e., s<sub>left</sub> + s<sub>right</sub> = s) and the number of distinct letters in s<sub>left</sub> and s<sub>right</sub> is the same.
Return the number of good splits you can make in `s`.
Example 1:
Input: s = "aacaba"
Output: 2
Explanation: There are 5 ways to split "aacaba" and 2 of them are good.
("a", "acaba") Left string and right string contains 1 and 3 different letters respectively.
("aa", "caba") Left string and right string contains 1 and 3 different letters respectively.
("aac", "aba") Left string and right string contains 2 and 2 different letters respectively (good split).
("aaca", "ba") Left string and right string contains 2 and 2 different letters respectively (good split).
("aacab", "a") Left string and right string contains 3 and 1 different letters respectively.
Example 2:
Input: s = "abcd"
Output: 1
Explanation: Split the string as follows ("ab", "cd").
Constraints:
-
1 ⇐ s.length ⇐ 105 -
sconsists of only lowercase English letters.