import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.*;

public class Solution {

  public static void main(String[] args) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String[] split = br.readLine().split(" ");
    long a = Long.valueOf(split[0]);
    long b = Long.valueOf(split[1]);
    long t = Long.valueOf(split[2]);
    
    System.out.println(BigInteger.valueOf((a + b) / 2)
        .modPow(BigInteger.valueOf(t), BigInteger.valueOf(1000000007L)).toString());
  }
}