Given an integer array arr and an integer target, return the number of tuples (i, j, k) such that i < j < k and arr[i] + arr[j] + arr[k] is equal to target.

Since the result can be very large, return the answer modulo $10^9 + 7$.

Constraints:

• $3 \leq$ arr.length $\leq 3000$

• $0 \leq$ arr[i] $\leq 100$

• $0 \leq$ target $\leq 300$

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.