You are given a tetrahedron. Let's mark its vertices with letters A, B, C and D correspondingly.

<image>

An ant is standing in the vertex D of the tetrahedron. The ant is quite active and he wouldn't stay idle. At each moment of time he makes a step from one vertex to another one along some edge of the tetrahedron. The ant just can't stand on one place.

You do not have to do much to solve the problem: your task is to count the number of ways in which the ant can go from the initial vertex D to itself in exactly n steps. In other words, you are asked to find out the number of different cyclic paths with the length of n from vertex D to itself. As the number can be quite large, you should print it modulo 1000000007 (109 + 7). 

Input

The first line contains the only integer n (1 ≤ n ≤ 107) — the required length of the cyclic path.

Output

Print the only integer — the required number of ways modulo 1000000007 (109 + 7).

Examples

Input

2


Output

3


Input

4


Output

21

Note

The required paths in the first sample are: 

  * D - A - D
  * D - B - D
  * D - C - D
/*
 * Remember a 6.0 student can know more than a 10.0 student.
 * Grades don't determine intelligence, they test obedience. 
 * I Never Give Up.
 * I will become Candidate Master.
 * I will defeat Saurabh Anand.
 * Skills are Cheap,Passion is Priceless.
 */
import java.util.*;
import java.util.Map.Entry;
import java.io.*;

import static java.lang.System.out;
import static java.util.Arrays.*;
import static java.lang.Math.*;

public class ContestMain{
	private static Reader in=new Reader();
	private static StringBuilder ans=new StringBuilder();
	private static long MOD=1000000000+7;// 1e9+7
	private static final int N=10000000+7; // 2e5+7
//    private static final double EPS=1e-9;
//    private static final int LIM=26;
//    private static final double PI=3.1415;
//    private static ArrayList<Integer> v[]=new ArrayList[N];
//    private static int color[]=new int[N];
	private static boolean mark[]=new boolean[N];

//    private static BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
//    private static ArrayList<Pair> v[]=new ArrayList[N];
	private static long powmod(long x,long n){
		if(n==0||x==0)
			return 1;
		else if(n%2==0)
			return(powmod((x*x)%MOD,n/2));
		else
			return (x*(powmod((x*x)%MOD,(n-1)/2)))%MOD;
	}

	private static void shuffle(long[] arr){
		for(int i=arr.length-1;i>=2;i--){
			int x=new Random().nextInt(i-1);
			long temp=arr[x];
			arr[x]=arr[i];
			arr[i]=temp;
		}
	}

//    private static long gcd(long a, long b){
//        if(b==0)return a;
//        return gcd(b,a%b);
//    }
//    private static boolean check(int x,int y){
//        if((x>=0&&x<n)&&(y>=0&&y<m)&&mat[x][y]!='X'&&!visited[x][y])return true;
//        return false;
//    }
	public static void main(String[] args) throws IOException{
		int n=in.nextInt();
		long dp[][]=new long[2][2];
		dp[0][0]=1;dp[0][1]=0;
		int c=0;
		for(int i=1;i<=n;++i){
			dp[c^1][0]=(3*dp[c][1])%MOD;
			dp[c^1][1]=(dp[c][0]+(2*(dp[c][1])%MOD))%MOD;
			c^=1;
		}
		if(n%2==0)out.println(dp[0][0]);
		else out.println(dp[1][0]);
	}
	static class Pair<T> implements Comparable<Pair>{
		int l;
		int r;

		Pair(){
			l=0;
			r=0;
		}

		Pair(int k,int v){
			l=k;
			r=v;
		}

		@Override
		public int compareTo(Pair o){
			if(o.l!=l)
				return (int)(l-o.l);
			else
				return (int)(r-o.r);
		}
		// Fenwick tree question comparator
//        @Override
//        public int compareTo(Pair o) {
//            if(o.r!=r)return (int) (r-o.r);
//            else return (int)(l-o.l);
//        }
	}

	static class Reader{
		BufferedReader br;
		StringTokenizer st;

		public Reader(){
			br=new BufferedReader(new InputStreamReader(System.in));
		}

		String next(){
			while(st==null||!st.hasMoreElements()){
				try{

					st=new StringTokenizer(br.readLine());
				}catch(IOException e){
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt(){
			return Integer.parseInt(next());
		}

		long nextLong(){
			return Long.parseLong(next());
		}

		double nextDouble(){
			return Double.parseDouble(next());
		}

		String nextLine(){
			String str="";
			try{
				str=br.readLine();
			}catch(IOException e){
				e.printStackTrace();
			}
			return str;
		}
	}
}