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

public class Solution {

   public static void main(String args[]){
        int a, b;
        BigInteger t;
        Scanner s = new Scanner(System.in);
        a = s.nextInt();
        b = s.nextInt();
        int val = (int) (.5 * (a + b));
        BigInteger base = new BigInteger(Integer.toString(val));
        BigInteger mod = new BigInteger("1000000007");
        t = s.nextBigInteger();
        BigInteger res = base.modPow(t, mod);
        System.out.println(res.toString());
        
    }//end main
}