#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

#define ull unsigned long long int;

unsigned long long int myPower(unsigned long long int x, unsigned long long int y)
{
	unsigned long long int res = 1;

	while (y > 0)
	{

		if (y%2 == 1)
			res = (res*x) % 1000000007;

		y = y / 2;
		x *= x;
		x = x % 1000000007;
	}
	return res;
}

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
	int a, b;
	cin >> a >> b;
	unsigned long long int t, last = 0, t2;
	cin >> t;
	int x = (a + b) / 2;

	last = myPower(x, t);
    
    cout << last % 1000000007 << endl;
    return 0;
}