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

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        BigInteger t = new BigInteger(sc.next());
        int c = (a + b)/2;
        BigInteger base = new BigInteger("" + c);
        BigInteger result = base.modPow(t, new BigInteger("1000000007"));
        System.out.println(result);
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
    }
}