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
import java.text.DecimalFormat;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.math.MathContext;

import static java.lang.Math.*;
import static java.util.Arrays.*;
import static java.util.Arrays.fill;
import static java.util.Collections.*;

public class Main {
    public static void main(String[] args) throws Exception {
        InputReader in = new InputReader(System.in);
        PrintWriter out = new PrintWriter(System.out);
        TaskA solver = new TaskA();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskA {
        int[] dx = {1, 0, -1, 0, -1, -1, 1, 1},
                dy = {0, 1, 0, -1, -1, 1 - 1, 1};
        int MAX = (int) (1e5 + 10);

        // GCD && LCM
        long gcd(long a, long b) {
            return b == 0 ? a : gcd(b, a % b);
        }

        long lcm(long a, long b) {
            return a * (b / gcd(a, b));
        }

        // REverse a String
        String rev(String s) {
            return new StringBuilder(s).reverse().toString();
        }


        public long memo[][],MAXx;

        /*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ SOLUTION IS RIGHT HERE^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
        public void solve(int testNumber, InputReader in, PrintWriter out) throws IOException {
            int n = in.nextInt();
            MAXx = (int)(1e9+7);
            memo = new long[4][4];
            /*for(int i = 0; i < 4; i++)
                fill(memo[i],-1);*/

            memo[1][1] = 1;
            memo[2][1] = 1;
            memo[3][1] = 1;
            int var = 0,xvar=1;
            for(int i =2; i <= n; i++){
                    memo[0][var] = (memo[1][xvar]+memo[2][xvar]+memo[3][xvar])%MAXx;
                    memo[1][var] = (memo[0][xvar]+memo[2][xvar]+memo[3][xvar])%MAXx;
                    memo[2][var] = (memo[1][xvar]+memo[0][xvar]+memo[3][xvar])%MAXx;
                    memo[3][var] = (memo[1][xvar]+memo[2][xvar]+memo[0][xvar])%MAXx;
                    var^=1;
                    xvar^=1;
            }
            out.println(memo[0][xvar]);
        }
    }
    static class pair implements Comparable<pair>{
        public Integer x,y,total;
        public pair(int x,int y,int z){
            this.x = x;
            this.y = y;
            this.total = z;
        }
        public pair(){x=0; y=0; total = x+y;}
        public int compareTo(pair that) {
            if(this.x != that.x)
                return this.x.compareTo(that.x);
            else
                return this.y.compareTo(that.y);
        }
    }
    /*^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^`````````````````````````^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^*/
    static class InputReader {
        private byte[] buf = new byte[8000];
        private int index;
        private int total;
        private InputStream in;
        // BufferedReader br = new BufferedReader(new
        // InputStreamReader(System.in));

        public InputReader(InputStream stream) {
            in = stream;
        }

        public int scan() {
            if (total == -1)
                throw new InputMismatchException();
            if (index >= total) {
                index = 0;
                try {
                    total = in.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (total <= 0)
                    return -1;
            }
            return buf[index++];
        }

        public long scanlong() {
            long integer = 0;
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            int neg = 1;
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n)) {
                if (n >= '0' && n <= '9') {
                    integer *= 10;
                    integer += n - '0';
                    n = scan();
                } else
                    throw new InputMismatchException();
            }
            return neg * integer;
        }

        private int scanInt() {
            int integer = 0;
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            int neg = 1;
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n)) {
                if (n >= '0' && n <= '9') {
                    integer *= 10;
                    integer += n - '0';
                    n = scan();
                } else
                    throw new InputMismatchException();
            }
            return neg * integer;
        }

        public double scandouble() {
            double doubll = 0;
            int n = scan();
            int neg = 1;
            while (isWhiteSpace(n))
                n = scan();
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n) && n != '.') {
                if (n >= '0' && n <= '9') {
                    doubll *= 10;
                    doubll += n - '0';
                    n = scan();
                }
            }
            if (n == '.') {
                n = scan();
                double temp = 1;
                while (!isWhiteSpace(n)) {
                    if (n >= '0' && n <= '9') {
                        temp /= 10;
                        doubll += (n - '0') * temp;
                        n = scan();
                    }
                }
            }
            return neg * doubll;
        }

        private float scanfloat() {
            float doubll = 0;
            int n = scan();
            int neg = 1;
            while (isWhiteSpace(n))
                n = scan();
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n) && n != '.') {
                if (n >= '0' && n <= '9') {
                    doubll *= 10;
                    doubll += n - '0';
                    n = scan();
                }
            }
            if (n == '.') {
                n = scan();
                double temp = 1;
                while (!isWhiteSpace(n)) {
                    if (n >= '0' && n <= '9') {
                        temp /= 10;
                        doubll += (n - '0') * temp;
                        n = scan();
                    }
                }
            }
            return neg * doubll;
        }

        public String scanstring() {
            StringBuilder sb = new StringBuilder();
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            while (!isWhiteSpace(n)) {
                sb.append((char) n);
                n = scan();
            }
            return sb.toString();
        }

        public String scan_nextLine() {
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            StringBuilder res = new StringBuilder();
            do {
                res.appendCodePoint(n);
                n = scan();
            } while (!isEndOfLine(n));
            return res.toString();
        }

        public boolean isWhiteSpace(int n) {
            if (n == ' ' || n == '\n' || n == '\r' || n == '\t' || n == -1)
                return true;
            return false;
        }

        private boolean isEndOfLine(int c) {
            return c == '\n' || c == '\r' || c == -1;
        }
        /// Input module

        public int nextInt() {
            return scanInt();
        }

        public long nextLong() {
            return scanlong();
        }

        public double nextDouble() {
            return scandouble();
        }

        public float nextFloat() {
            return scanfloat();
        }

        public String next() {
            return scanstring();
        }

        public String nextLine() throws IOException {
            return scan_nextLine();
        }

        public int[] readintArray(int size) {
            int[] array = new int[size];
            for (int i = 0; i < size; i++) {
                array[i] = nextInt();
            }
            return array;
        }

        public Integer[] readIntegerArray(int size) {
            Integer[] array = new Integer[size];
            for (int i = 0; i < size; i++) {
                array[i] = nextInt();
            }
            return array;
        }
    }

} 