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

public class Solution {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        BigInteger mod = new BigInteger("1000000007");
        int a = scan.nextInt();
        int b = scan.nextInt();
        
        String t_str = scan.next(); // Big
        
        BigInteger t = new BigInteger(t_str);
        BigInteger exp = BigInteger.valueOf(a + b).divide(BigInteger.valueOf(2)).modPow(t,mod);
        System.out.println(exp);
         
        
        
    }
}