Count possible ways to construct buildings.java

class Solution
{
    public int TotalWays(int n)
    {
        int mod = 1000000007;
        long[] dp = new long[n + 1];
        dp[0] = 1;
        dp[1] = 2;
        for (int i = 2; i <= n; i++) {
            dp[i] = (dp[i - 1] + dp[i - 2]) % mod;
        }
        return (int)((dp[n] * dp[n]) % mod);
    }
}