You are given an integer array nums, where each element is a single digit.

The triangular sum of nums is computed by executing the following procedure:

1. If nums has a length of $1$, end the process and return nums[0].

2. Otherwise, construct a new integer array newNums of length nums.length $- 1$.

3. For every index i such that $0 \leq$ i $<$ nums.length $- 1$, assign newNums[i] = (nums[i] + nums[i + 1]) % $10$, where % denotes the modulo operation.

4. Replace nums with newNums.

5. Repeat the process until only $1$ element remains in nums.

Return the triangular sum of nums.

Constraints:

• $1 \leq$ nums.length $\leq 1000$

• $0 \leq$ nums[i] $\leq 9$

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.