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Python Recursion
What are recursive functions?
Until now we had been defining a feature and on the time of execution, we had been calling it from out of doors the feature. What if we name the feature in the feature? it's going to create a kinda loop that what recursion capabilities are all about.
A recursive feature is that feature that can name itself all through execution. For example, whilst a feature frame has a declaration wherein it's miles calling itself then that feature can be termed as a recursive feature.
We have stated that recursion act like loops what can carry out repetitive paintings so there need to be a base situation that prevents that repetitive declaration and provide a end result otherwise you may get entice within side the limitless loop.
Go this blog on bubble sort program in c using function to know how the function works with examples.
Let’s code
def fact(n):
if n==1 or n==0: #Base condition
return 1
else:
return n * fact(n-1) # recursion function calling
num=7
print("the factorial of" ,num, "is ", fact(num)) #function callingOutput
the factorial of 7 is 5040Work behind the code:
In the above example to execute the function fact(), we call it from outside the function then the value of variable num gets assigned to the function argument n and function gets started to execute when the argument n does not satisfy the if statement the else statement gets executed. In the else statement we strike the recursive function and let’s see how does it work.
fact(n) #main function
return 7 * fact(6) #recursive function first call
return 7 * 6 *fact(5) #recursive function 2nd call (the value of fact(6) is 6 * fact(5))
return 7*6*5*fact(4) #recursive function 3rd call
return 7*6*5*4 *fact(3) #recursive function 4th call
return 7*6*5*4*3*fact(2) #recursive function 5th call
return 7*6*5*4*3*2*fact(1) #recursive function 6th call
return 7*6*5*4*3*2*1 #recursive function 7th callAdvantages:
Disadvantages:
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