You are given an $n imes n$ grid representing a layout of $1 imes 1 imes 1$ unit cubes placed on top of each other. Each value grid[i][j] represents the number of cubes stacked vertically on the cell at row i and column j.

Return the total surface area of the resulting $3 ext{D}$ shape formed by all the cubes.

Constraints:

• n $==$ grid.length $==$ grid[i].length

• $1 \leq$ n $\leq 50$

• $0 \leq$ grid[i][j] $\leq 50$

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.