1
def __init__(self):
self.a,self.b = 0 ,1 # 初始化两个计数器a，b
def __iter__(self): # 实例本身就是迭代对象，故返回自己
return self
def __next__(self):
self.a,self.b = self.b,self.a+self.b # 计算下一个值
if self.a > 100: # 退出循环的条件
raise StopIteration()
return self.a # 返回下一个值
for n in Fib():
print(n)
2.单个输出第t个数
def fib(num):
a,b,c=1,1,0
if num <=0:
print ('wrong')
if num > 0 and num <= 2:
print ('1')
else:
while num > 2:
a,b =b,a+b
num = num-1
print (b)
return 0
t = 3
fib(t)
注意：a,b = b,a+b相当于（a,b）= (b,a+b)
3.从第一位输出直到第n个数
def fib(max):
n, a, b = 0, 0, 1
while n < max:
print(b)
a, b = b, a + b
n = n + 1
return 'done'
>>> fib(6)
1
1
2
3
5
8
'done'
