#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#define M 1000000007

long long int ipow(long long int base,long long int exp)
{
    long long int result = 1;
    while (exp)
    {
        if (exp & 1)
            result =(result%M* base%M)%M;
        exp >>= 1;
        base=((base%M)* (base%M))%M;
    }

    return result;
}

int main() {

    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
    long long int a,b,t,x,ans,c;
    scanf("%lld%lld%lld",&a,&b,&t);
    c=(a+b)/2;
    ans=ipow(c,t)%M;
    printf("%lld\n",ans);
    return 0;
}