You have two types of tiles: a
2 x 1 domino shape and a tromino shape. You may rotate these shapes.
Given an integer n, return the number of ways to tile an
2 x n board. 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 Output: 5 Explanation: The five different ways are show above.
Input: n = 1 Output: 1
1 <= n <= 1000