函数递归

函数递归

• 函数递归：函数重复地调用自己，这叫递归。

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  # 函数不断地内部调用 def d():     return '232'   def c():     r = d()     return r   def b():     r = c()     return r   def a():     r = b()     print(r) a()   ----- 232

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  #函数重复调用自己，叫做递归 def func(n):     n +=1     if n >= 5:         return 'a'     return func(n)   r = func(1) print(r)   ----- a

• 使用递归 7*6*5*4*3*2*1​

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  #方法一 def factorial(num):        if num>1:         return num*factorial(num-1)     else:         return 1    sum =factorial(7) print(sum) ------ 5040

• 阶乘变换（11*9*7*5*3*1）(12*10*8*6*4*2)

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  def fa1(a):       if a%2 == 0:         if a > 2:             return a*fa1(a-2)         else:             return 2         pass     else:         if a > 1:             return a*fa1(a-2)         else:             return 1   b = fa1(11) c = fa1(12) print(b,c) ----- 10395 46080

  
  

  
  

来自为知笔记(Wiz)