You are given a $0$ indexed integer array nums.

The distinct count of a subarray of nums is defined as the number of unique elements present in that subarray.

Return the sum of the squares of distinct counts across all subarrays of nums.

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

Constraints:

• $1 \leq$ nums.length $\leq 10^5$

• $1 \leq$ nums[i] $\leq 10^5$

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.