# 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%1000000007)*(temp%1000000007))%1000000007
	else:
		return (((x%1000000007)*(temp%1000000007))%1000000007*temp%1000000007)%1000000007

a,b,t = map(int,raw_input().split())
print int(power((a+b)/2,t))