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

int modulo_exponent(long long int b, long long int e, long long int m){
    //Return (b^e)%m
    long long int half_exp;
    long long int big_num, big_num_mod, big_num_mod_b; 
    
    if (e==0)
        return 1;
    
    half_exp = modulo_exponent(b, e/2, m);
    
    //cout << b << "^" << e/2 << "%" << m << "=" << half_exp << endl;
    
    big_num = (half_exp * half_exp);
    big_num_mod = big_num % m;
    big_num_mod_b = (b* big_num_mod)%m;
   // cout << "(" << b << "^" << e/2 << "%" << m << ") squared ="  << big_num << endl;
    //cout << "(" << b << "^" << e/2 << "%" << m << ") squared % m ="  << big_num_mod << endl;
        
    if (e%2 == 0)
        return big_num_mod;
    else
        return big_num_mod_b;
}

int main() {
    int a, b;
    long long int t;
    int modulo = 1000000007;
    cin >> a >> b >> t;
    
    double avg_growth = ((a*1.0)+(b*1.0))/2.0;
    
    cout << modulo_exponent(avg_growth, t, modulo);
    
    return 0;
}