python防止栈溢出的实例讲解

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deffact(n):

returnfact_iter(n,1)

deffact_iter(num, product):

ifnum==1:

returnproduct

returnfact_iter(num-1, num*product)

# fact(5)的调用过程

===> fact_iter(5,1)

===> fact_iter(4,5)

===> fact_iter(3,20)

===> fact_iter(2,60)

===> fact_iter(1,120)

===>120

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>>> fact(1000)

Traceback (most recent call last):

File"<stdin>", line1,in<module>

File"<stdin>", line4,infact

...

File"<stdin>", line4,infact

RuntimeError: maximum recursion depth exceeded