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) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */   Scanner scan = new Scanner(System.in);
        int a = scan.nextInt();
        int b = scan.nextInt();
        long t = scan.nextLong();

        int virus = (a + b) / 2;
        int modul = (int)Math.pow(10, 9) + 7;

        //long res = (long) power(virus, t, modul);
        int res = modulo(virus, t, modul);
        System.out.println(res);
    }
    static int modulo(int a,long b,int c) {
        long x=1;
        long y=a;
        while(b > 0){
            if(b%2 == 1L){
                x=(x*y)%c;
            }
            y = (y*y)%c; // squaring the base
            b /= 2;
        }
        return (int) x%c;
    
    }
}