a,b,t = map(int, raw_input().strip().split(" "))
m = 1000000007
factor = (a+b)/2

def fastPower(base,power,M):
    if power==0:
        return 1
    if power==1:
        return base
    halfn=fastPower(base,power/2,M)
    if power%2==0:
        return ( halfn * halfn ) % M;
    else:
        return ( ( ( halfn * halfn ) % M ) * base ) % M;

print fastPower(factor,t,m)