import java.util.Scanner;

public class Solution {
    private static final int M = 1000000000 + 7;
    
    public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            byte a = scanner.nextByte();
            byte b = scanner.nextByte();
            long t = scanner.nextLong();
            int c = (a + b) / 2;
            long result = powMod(c, t);
            System.out.println(result);
        }
    }
    
    public static long powMod(long n, long k) {
        if (k == 1) {
            return n % M;
        }
        if (k % 2 == 0) {
            return powMod((n * n) % M, k / 2) % M;
        }
        return (n * powMod(n, k - 1)) % M;
    }
}