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 scanner = new Scanner(System.in);
        long a = scanner.nextInt();
        long b = scanner.nextInt();
//        long t = scanner.nextInt();
        BigInteger t = new BigInteger(scanner.next());
        //(.5*(a+b))^t
//        BigInteger base =new BigInteger(String.valueOf((a+b)/2));
        BigInteger m = new BigInteger(String.valueOf(1000000007));
//        long base = (a+b)/2;
//        long v = expo(base,t);
        BigInteger base = new BigInteger(String.valueOf((int) (0.5*(a+b))));
        BigInteger result = base.modPow(t,m);
        System.out.print(result);
    }
}