// By J.D. Sandifer - 2016-07-27

// Trying built-in BigInteger and modPow function.
// Why reinvent the wheel?

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

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int a = in.nextInt(); 
        int b = in.nextInt();  
        long endTime = in.nextLong();
        in.close();
        
        BigInteger growthRate = BigInteger.valueOf((a + b) / 2);
        BigInteger bigTime = BigInteger.valueOf(endTime);
        BigInteger modulator = BigInteger.valueOf((long) Math.pow(10, 9) + 7);
        
        BigInteger cells = growthRate.modPow(bigTime, modulator);
                    
        System.out.println(cells.intValue());
    }
}