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

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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.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.io.BufferedOutputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;

public class Main {

    public static void main(String[] args) {
        if (args.length > 0 && args[0].toLowerCase().equals("local")) {
            try {
                System.setIn(new FileInputStream("input.txt"));
                System.setOut(new PrintStream(new File("output.txt")));
            } catch (IOException exc) {
            }
        }
        Task task = new Task();
        task.solve();
    }

    public static class Task {
        static final long MOD = (long) 1e9 + 7;
        static final PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));
        // [{2, 3}, {1, 0}]
        int[][] base = { { 2, 3 }, { 1, 0 } };

        public void solve() {
            try {
                Scan sc = new Scan();
                int n = (int) sc.scanLong();
                if (n == 1) {
                    out.println(0);
                    return;
                }
                if (n == 2) {
                    out.println(3);
                    return;
                }
                int[][] exp = fastExp(base, n - 2);
                long ans = exp[0][0] * (long) 3;
                ans %= MOD;
                out.println(ans);
            } finally {
                out.close();
            }
        }

        private int[][] fastExp(int[][] a, int pow) {
            if (pow == 1)
                return a;

            if (pow % 2 == 0) {
                return fastExp(mult(a, a), pow / 2);
            } else {
                return mult(fastExp(mult(a, a), pow / 2), a);
            }
        }

        private int[][] mult(int[][] a, int[][] b) {
            int a_rows = a.length;
            int a_cols = a[0].length;
            int b_cols = b[0].length;
            int[][] res = new int[a_rows][b_cols];
            for (int i = 0; i < a_rows; ++i) {
                for (int j = 0; j < b_cols; ++j) {
                    int tres = 0;
                    for (int k = 0; k < a_cols; ++k) {
                        long mul = a[i][k] * (long) b[k][j];
                        mul %= MOD;
                        tres += mul;
                        if (tres >= MOD)
                            tres -= MOD;
                    }
                    res[i][j] = tres;
                }
            }
            return res;
        }

        private void debug(Object... x) {
            StringBuilder sb = new StringBuilder();
            for (Object o : x)
                sb.append(String.valueOf(o)).append(" ");
            out.println(sb);
        }
    }

    public static class Scan {
        private byte[] buf = new byte[1024];
        private int index;
        private InputStream in;
        private int total;

        public Scan() {
            in = System.in;
        }

        public int scan() {
            if (total < 0)
                throw new InputMismatchException();
            if (index >= total) {
                index = 0;
                try {
                    total = in.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                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;
        }

        public double scanDouble() {
            double doub = 0;
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            int neg = 1;
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n) && n != '.') {
                if (n >= '0' && n <= '9') {
                    doub *= 10;
                    doub += n - '0';
                    n = scan();
                } else
                    throw new InputMismatchException();
            }
            if (n == '.') {
                n = scan();
                double temp = 1;
                while (!isWhiteSpace(n)) {
                    if (n >= '0' && n <= '9') {
                        temp /= 10;
                        doub += (n - '0') * temp;
                        n = scan();
                    } else
                        throw new InputMismatchException();
                }
            }
            return doub * neg;
        }

        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 char scanChar() {
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            return (char) n;
        }

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