import java.util.*;
import java.lang.Math.*;
import java.math.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int a = sc.nextInt();
        int b = sc.nextInt();
        long t = sc.nextLong();
        BigDecimal term1 = (BigDecimal.valueOf(0.5)).multiply((BigDecimal.valueOf(a)).add(BigDecimal.valueOf(b)));
        BigInteger term2 = (term1.toBigInteger()).modPow(BigInteger.valueOf(t),BigInteger.valueOf(1000000007));
        //term1 = term1.pow(t);
        //BigInteger term2 = (term1.toBigInteger()).mod(BigInteger.valueOf(1000000007));
        System.out.print(term2);
    }
}