You are given two strings, s and sub, along with a $2 ext{D}$ character array mappings where mappings[i] $= [ ext{old}_i, ext{new}_i]$ indicates that any occurrence of the character $ ext{old}_i$ in sub can be replaced with $ ext{new}_i$. Each character in sub may be replaced at most once, and characters in s cannot be replaced.

Return true if it is possible to make sub a substring of s after replacing zero or more characters in sub using the given mappings. Otherwise, return false.

Note: A substring is a contiguous non empty sequence of characters within a string.

Constraints:

• $1 \leq$ sub.length $\leq$ s.length $\leq 5000$

• $0 \leq$ mappings.length $\leq 1000$

• mappings[i].length $= 2$

• $ ext{old}_i \neq ext{new}_i$

• s and sub consist of uppercase and lowercase English letters and digits.

• $ ext{old}_i$ and $ ext{new}_i$ are either uppercase or lowercase English letters or digits.

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.