A DNA sequence consists of a series of nucleotides, each represented by one of the characters 'A', 'C', 'G', or 'T'.

Given a string s representing a DNA sequence, find and return all $10$-letter-long substrings that appear more than once within s. The result may be returned in any order.

Constraints:

• $1 \leq$ s.length $\leq 10^5$

• s[i] is one of 'A', 'C', 'G', or 'T'

Now, let’s take a moment to make sure you’ve correctly understood the problem. The quiz below helps you check if you’re solving the correct problem:

We have a game for you to play. Rearrange the logical building blocks to develop a clearer understanding of how to solve this problem.

Implement your solution in the following coding playground.