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

import java.math.*;

public class Solution {

    public static void main(String[] args) {
    		Scanner s = new Scanner(System.in);
		int a =s.nextInt();
		int b = s.nextInt();
		BigInteger T=new BigInteger(s.nextLine().trim()) ;
		BigInteger actualCells=null;
		
			actualCells=BigInteger.valueOf((a+b)/2).modPow(T, BigInteger.valueOf(1000000007));
        
		System.out.println(actualCells);
		

		
    }
}