python-14 递归函数和函数调用原理

函数调用

函数调用执行流程

递归Recursion

斐波那契数列

RecursionError
Ipython 栈空间3000 ，python 栈空间1000
sys.getrecursionLimit()

pro = 1 
def fn1(n):    #  3 ;  2   1 
   if n == 1 :  #  
       return 1   #  1 
   global pro
   pro *= n     #  3   2  
   return  fn1(n-1)  #  2   1 

def fn1(n):   
   if n == 0 or n == 1 :  
       return 1  
   return n*fn1(n-1)

 def factorial(n):
       if n <= 2 :
           return n 
       return n * factorial(n-1)
   	
------------------------
n = 5 
f = 1 

for i in range(n, 0, -1):
   f *= i
   print(f)
   
-----------------------	
def factorial(n, f=1):
   f *= n
   if n == 1 :
       return f 
   return factorial(n-1, f)

def peach(days=10):
   if days == 1 :
       return 1
   return  2 * (peach(days-1) + 1)