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

public class Solution {
  private static long mod(long a) {
    return a % 1000000007;
  }
  
  private static long fastPow(long b, long n) {
    if (n == 0) {
      return 1;
    }
    if (n == 1) {
      return b;
    }
    long h = fastPow(b, n / 2);
    long f = mod(h * h);
    if (n % 2 == 0) {
      return f;
    }
    return mod(f * b);
  }

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