Given N, the number of plots on either sides of the road. Find the total ways to construct buildings in the plots such that there is a space between any 2 buildings. All plots on one side of the road are continuous.
Lets suppose ‘*’ represents a plot, then for N=3, the plots can be represented as * * * | | * * *
Where | | represents the road.
Note: As the answer can be very large, print it mod 1000000007
Input: N = 3 Output: 25 Explanation: 3 plots, which means possible ways for one side are BSS, BSB, SSS, SBS, SSB where B represents a building and S represents an empty space Total possible ways are 25, because a way to place on one side can correspond to any of 5 ways on other side.
Input: N = 10 Output: 20736 Explanation: There are 20736 ways for N = 10.
You don't need to read or print anything. Your task is to complete the function ToralWays() which takes N as input parameter and returns the total possible ways modulo 109 + 7.
Expected Time Complexity: O(N)
Expected Space Complexity: O(N)
1 <= N <= 100000
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