def ft_pow(nb, n):
    if n == 0:
        return 1
    tmp = ft_pow(nb, n/2)
    if n % 2 == 0:
        return (tmp * tmp) % 1000000007
    else:
        if n > 0:
            return (nb * tmp * tmp) % 1000000007
        else:
            return (tmp * tmp / nb) % 1000000007

a,b,t = [int(x) for x in raw_input().split(' ')]
cnt = 1
k = (a + b) / 2
print ft_pow(k,t)