public class Solution
extends Object
1411 - Number of Ways to Paint N × 3 Grid\.
Hard
You have a `grid` of size `n x 3` and you want to paint each cell of the grid with exactly one of the three colors: **Red** , **Yellow, ** or **Green** while making sure that no two adjacent cells have the same color (i.e., no two cells that share vertical or horizontal sides have the same color).
Given `n` the number of rows of the grid, return _the number of ways_ you can paint this `grid`. As the answer may grow large, the answer **must be** computed modulo 109 + 7.
**Example 1:**

**Input:** n = 1
**Output:** 12
**Explanation:** There are 12 possible way to paint the grid as shown.
**Example 2:**
**Input:** n = 5000
**Output:** 30228214
**Constraints:**
* `n == grid.length`
* `1 <= n <= 5000`