largest-substring-between-two-equal-characters

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1624. Largest Substring Between Two Equal Characters (Easy)

Given a string s, return the length of the longest substring between two equal characters, excluding the two characters. If there is no such substring return -1.

A substring is a contiguous sequence of characters within a string.

 

Example 1:

Input: s = "aa"
Output: 0
Explanation: The optimal substring here is an empty substring between the two 'a's.

Example 2:

Input: s = "abca"
Output: 2
Explanation: The optimal substring here is "bc".

Example 3:

Input: s = "cbzxy"
Output: -1
Explanation: There are no characters that appear twice in s.

 

Constraints:

• 1 <= s.length <= 300
• s contains only lowercase English letters.

Related Topics

[Hash Table] [String]

Hints

Hint 1

Try saving the first and last position of each character

Hint 2

Try finding every pair of indexes with equal characters