import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        Scanner get=new Scanner(System.in);
        int a=get.nextInt();
        int b=get.nextInt();
        long t=get.nextLong();
        int  x=(int) (0.5*a+0.5*b);
        long num=1;
        int mod=1000000007;
        num=fastpow(x,t-1,mod);
        //System.out.println(den);
        System.out.println((num*x)%mod);
        
    }
    public static long fastpow(long a,long b,int mod)
        {
     
        long ans=1;
        while(b!=0)
         {
            if(b%2==1)
                {
                ans=(ans*a)%mod;
                }
            a*=a;
            a%=mod;
            b/=2;
        }
        return ans;
}
}