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.*;
import java.math.*;
import java.util.*;


public class Main {

    static class ProblemSolver {
        int MOD = 1000000007;

        public void solveTheProblem(InputReader in, OutputWriter out) {
//            int test = in.nextInt();
            int test = 1;
            for (int t = 0; t < test; t++) {
                Solve(in, out);
            }
        }

        public void Solve(InputReader in, OutputWriter out) {
            long count = 0;
            int n = in.nextInt();

            if (n == 1) {
                out.println(0);
                return;
            } else if (n == 2) {
                out.println(3);
                return;
            }

            long value = 2;
            for (int i = 3; i <= n; i++) {
                value = ((value + value + value + (i % 2 == 0 ? -1 : 1)) % MOD) % MOD;
            }
            out.println(value + (n % 2 == 0 ? 1 : -1));
        }
    }


    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        OutputWriter out = new OutputWriter(outputStream);
        ProblemSolver problemSolver = new ProblemSolver();
        problemSolver.solveTheProblem(in, out);
        out.flush();
        out.close();
    }
}

class InputReader {
    private boolean finished = false;

    private InputStream stream;
    private byte[] buf = new byte[1024];
    private int curChar;
    private int numChars;
    private SpaceCharFilter filter;

    public InputReader(InputStream stream) {
        this.stream = stream;
    }

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

    public int peek() {
        if (numChars == -1) {
            return -1;
        }
        if (curChar >= numChars) {
            curChar = 0;
            try {
                numChars = stream.read(buf);
            } catch (IOException e) {
                return -1;
            }
            if (numChars <= 0) {
                return -1;
            }
        }
        return buf[curChar];
    }

    public int nextInt() {
        int c = read();
        while (isSpaceChar(c)) {
            c = read();
        }
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        int res = 0;
        do {
            if (c < '0' || c > '9') {
                throw new InputMismatchException();
            }
            res *= 10;
            res += c - '0';
            c = read();
        } while (!isSpaceChar(c));
        return res * sgn;
    }

    public long nextLong() {
        int c = read();
        while (isSpaceChar(c)) {
            c = read();
        }
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        long res = 0;
        do {
            if (c < '0' || c > '9') {
                throw new InputMismatchException();
            }
            res *= 10;
            res += c - '0';
            c = read();
        } while (!isSpaceChar(c));
        return res * sgn;
    }

    public String nextString() {
        int c = read();
        while (isSpaceChar(c)) {
            c = read();
        }
        StringBuilder res = new StringBuilder();
        do {
            if (Character.isValidCodePoint(c)) {
                res.appendCodePoint(c);
            }
            c = read();
        } while (!isSpaceChar(c));
        return res.toString();
    }

    public char[] nextCharArr() {
        return nextString().toCharArray();
    }

    public boolean isSpaceChar(int c) {
        if (filter != null) {
            return filter.isSpaceChar(c);
        }
        return isWhitespace(c);
    }

    public static boolean isWhitespace(int c) {
        return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }

    private String readLine0() {
        StringBuilder buf = new StringBuilder();
        int c = read();
        while (c != '\n' && c != -1) {
            if (c != '\r') {
                buf.appendCodePoint(c);
            }
            c = read();
        }
        return buf.toString();
    }

    public String readLine() {
        String s = readLine0();
        while (s.trim().length() == 0) {
            s = readLine0();
        }
        return s;
    }

    public String readLine(boolean ignoreEmptyLines) {
        if (ignoreEmptyLines) {
            return readLine();
        } else {
            return readLine0();
        }
    }

    public BigInteger readBigInteger() {
        try {
            return new BigInteger(nextString());
        } catch (NumberFormatException e) {
            throw new InputMismatchException();
        }
    }

    public char nextCharacter() {
        int c = read();
        while (isSpaceChar(c)) {
            c = read();
        }
        return (char) c;
    }

    public double nextDouble() {
        int c = read();
        while (isSpaceChar(c)) {
            c = read();
        }
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        double res = 0;
        while (!isSpaceChar(c) && c != '.') {
            if (c == 'e' || c == 'E') {
                return res * Math.pow(10, nextInt());
            }
            if (c < '0' || c > '9') {
                throw new InputMismatchException();
            }
            res *= 10;
            res += c - '0';
            c = read();
        }
        if (c == '.') {
            c = read();
            double m = 1;
            while (!isSpaceChar(c)) {
                if (c == 'e' || c == 'E') {
                    return res * Math.pow(10, nextInt());
                }
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                m /= 10;
                res += (c - '0') * m;
                c = read();
            }
        }
        return res * sgn;
    }

    public boolean isExhausted() {
        int value;
        while (isSpaceChar(value = peek()) && value != -1) {
            read();
        }
        return value == -1;
    }

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

    public interface SpaceCharFilter {
        public boolean isSpaceChar(int ch);
    }

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

    public long[] nextLongArray(int n) {
        long[] array = new long[n];
        for (int i = 0; i < n; ++i) array[i] = nextLong();
        return array;
    }


}

class OutputWriter {
    private final PrintWriter writer;

    public OutputWriter(OutputStream outputStream) {
        writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
    }

    public OutputWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void print(char[] array) {
        writer.print(array);
    }

    public void print(Object... objects) {
        for (int i = 0; i < objects.length; i++) {
            if (i != 0) {
                writer.print(' ');
            }
            writer.print(objects[i]);
        }
    }

    public void print(int[] array) {
        for (int i = 0; i < array.length; i++) {
            if (i != 0) {
                writer.print(' ');
            }
            writer.print(array[i]);
        }
    }

    public void print(double[] array) {
        for (int i = 0; i < array.length; i++) {
            if (i != 0) {
                writer.print(' ');
            }
            writer.print(array[i]);
        }
    }

    public void print(long[] array) {
        for (int i = 0; i < array.length; i++) {
            if (i != 0) {
                writer.print(' ');
            }
            writer.print(array[i]);
        }
    }

    public void println(int[] array) {
        print(array);
        writer.println();
    }

    public void println(double[] array) {
        print(array);
        writer.println();
    }

    public void println(long[] array) {
        print(array);
        writer.println();
    }

    public void println() {
        writer.println();
    }

    public void println(Object... objects) {
        print(objects);
        writer.println();
    }

    public void print(char i) {
        writer.print(i);
    }

    public void println(char i) {
        writer.println(i);
    }

    public void println(char[] array) {
        writer.println(array);
    }

    public void close() {
        writer.close();
    }

    public void flush() {
        writer.flush();
    }

    public void print(long i) {
        writer.print(i);
    }

    public void println(long i) {
        writer.println(i);
    }

    public void print(int i) {
        writer.print(i);
    }

    public void println(int i) {
        writer.println(i);
    }

    public void yes() {
        println("YES");
    }

    public void no() {
        println("NO");
    }
}