#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
long power(long x, unsigned long y, long p)
{
    long res = 1;      // Initialize result
 
    x = x % p;  // Update x if it is more than or 
                // equal to p
 
    while (y > 0)
    {
        // If y is odd, multiply x with result
        if (y & 1)
            res = (res*x) % p;
 
        // y must be even now
        y = y>>1; // y = y/2
        x = (x*x) % p;  
    }
    return res;
}

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    long a = 0, b = 0, t = 0;
    cin >> a;
    cin >> b;
    cin >> t;
    
    long spread = power(0.5 * (a + b), t, 1000000007);
    cout << spread;
    return 0;
}