790. Domino and Tromino Tiling ⭐
You have two types of tiles: a
2 x 1domino shape and a tromino shape. You may rotate these shapes.
Given an integer n, return the number of ways to tile an
2 x nboard. Since the answer may be very large, return it modulo
109 + 7.
In a tiling, every square must be covered by a tile. Two tilings are different if and only if there are two 4-directionally adjacent cells on the board such that exactly one of the tilings has both squares occupied by a tile.
Input: n = 3
Explanation: The five different ways are show above.
Input: n = 1
1 <= n <= 1000