883 - Projection Area of 3D Shapes.

Easy

You are given an n x n grid where we place some 1 x 1 x 1 cubes that are axis-aligned with the x, y, and z axes.

Each value v = grid[i][j] represents a tower of v cubes placed on top of the cell (i, j).

We view the projection of these cubes onto the xy, yz, and zx planes.

A projection is like a shadow, that maps our 3-dimensional figure to a 2-dimensional plane. We are viewing the "shadow" when looking at the cubes from the top, the front, and the side.

Return the total area of all three projections.

Example 1:

Input: grid = \[\[1,2],3,4]

Output: 17

Explanation: Here are the three projections ("shadows") of the shape made with each axis-aligned plane.

Example 2:

Input: grid = \[\[2]]

Output: 5

Example 3:

Input: grid = \[\[1,0],0,2]

Output: 8

Constraints:

• n == grid.length == grid[i].length

• 1 <= n <= 50

• 0 <= grid[i][j] <= 50