# Enter your code here. Read input from STDIN. Print output to STDOUT
def power(x,y):
    if y==0:
        return 1
    temp=power(x,y/2)
    if(y%2==0):
        return ((temp%(10**9+7))*(temp%(10**9+7)))%(10**9+7)
    else:
        return (x*(temp%(10**9+7))*(temp%(10**9+7))) % (10**9 +7)

T=raw_input().split()
a=int(T[0])
b=int(T[1])
t=int(T[2])
avg=(a+b)/2
cells=1
cells = power(avg,t)
print cells%(10**9+7)