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 in=new Scanner(System.in);
        int a=in.nextInt();
        int b=in.nextInt();
        BigInteger t=new BigInteger(in.next());
        BigInteger base=new BigInteger(String.valueOf((a+b)/2));
        BigInteger mod=new BigInteger(String.valueOf(1000000000+7));
        base=base.modPow(t,mod);
        System.out.print(base.toString());
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
    }
}