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

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int a = in.nextInt();
        int b = in.nextInt();
        long t = in.nextLong();
        System.out.println(BigInteger.valueOf((a + b) / 2)
                .modPow(BigInteger.valueOf(t), BigInteger.valueOf(1000000007)));
    }
}