public class Solution
extends Object
892 - Surface Area of 3D Shapes\.
Easy
You are given an `n x n` `grid` where you have placed some `1 x 1 x 1` cubes. Each value `v = grid[i][j]` represents a tower of `v` cubes placed on top of cell `(i, j)`.
After placing these cubes, you have decided to glue any directly adjacent cubes to each other, forming several irregular 3D shapes.
Return _the total surface area of the resulting shapes_.
**Note:** The bottom face of each shape counts toward its surface area.
**Example 1:**
**Input:** grid = \[\[1,2],[3,4]]
**Output:** 34
**Example 2:**
**Input:** grid = \[\[1,1,1],[1,0,1],[1,1,1]]
**Output:** 32
**Example 3:**
**Input:** grid = \[\[2,2,2],[2,1,2],[2,2,2]]
**Output:** 46
**Constraints:**
* `n == grid.length == grid[i].length`
* `1 <= n <= 50`
* `0 <= grid[i][j] <= 50`