def f(k):
if k<=3:
print(k)
return
for i in range(1,4):
f(k-i)
return
执行语句f(6),则f(3)被调用的次数为( )
①a[i]=k ②a[i-1]=k ③a[i+1]=a[i] ④a[i]=a[i-1]
⑤for i in range(j,9) ⑥for i in range(8,j-2,-1)
划线处所需代码依次为( )
def cal(n):
if n <= 1:
return 1
if n % 2 == 0:
return 2*cal(n-1)
执行语句k=cal(5),则k的值为( )