HDU 1021 Fibonacci Again Pyhton实现

n=int(input())
a=7
b=11
c=a+b
if n==0:
    print(a)
elif n==1:
    print(b)
else:
    for i in range(1,n):
        t=b
        b=a+b
        a=t
    if b%3==0:
        print ('yes')
    else:
        print ('no')