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

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 in =new Scanner(System.in);
        int a=in.nextInt();
        int b=in.nextInt();
        long t=in.nextLong();
        long x=(long) (0.5*(a+b));
        long ans=power(x,t,1000000007);
        //int ans=(int)((0.5*a*t+0.5*b*t)%(Math.pow(10,9)+7));
        System.out.println(ans);
    }
  public static  long power(long x,  long y, long p)
{
    long res = 1;      // Initialize result
 
    x = x % p;  // Update x if it is more than or 
                // equal to p
 
    while (y > 0)
    {
        // If y is odd, multiply x with result
        if (y%2==1)
            res = (res*x) % p;
 
        // y must be even now
        y = y/2; // y = y/2
        x = (x*x) % p;  
    }
    return res;
}
}