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) {
        Scanner in = new Scanner(System.in);
        final double A_PROB = 0.5;
        final double B_PROB = 0.5;    
        final BigInteger MOD_CONSTANT = new BigInteger("1000000007");
        
        int a = in.nextInt();
        int b = in.nextInt();
        BigInteger t = new BigInteger(in.next());
        final int GROWTH_FACTOR = (int) ((A_PROB * a) + (B_PROB * b));
        
        BigInteger middleman = new BigInteger(String.valueOf(GROWTH_FACTOR));
        
        double numCells = 1;
        long answer = 0;      
        
        middleman = middleman.modPow(t, MOD_CONSTANT);
        
        answer = middleman.longValue();
        
        System.out.println(answer);
    }
}