A happy number is a number in which the eventual sum of the square of the digits of the number is equal to 1.

Q. A happy number is a number in which the eventual sum of the square of the digits of the number is equal to 1.

Example : 12 = (1)2+(2)2 =1+4=5
Hence , 12 is not a happy number

Example 100 = (1)2 + ( 0 )2 + ( 0 )2 = 1+ 0 + 0 = 1  
Hence , 100 is a happy number.

Write a program that takes a number and checks if it is a happy number by using following two functions in it :

Sum_sq_digits :returns the sum of the square of the digits of the number x, using the recursive technique

Ishappy() : checks if the given number is a happy number by calling the function sum_sq_digits and displays an appropriate message

Answer =

You can understand by Watching video :-

def sum_sq_digits (num,n= 0):
    if n == len(num) :
        return 0
    else :
        return ( int ( num [ n ] ) ) ** 2 + sum_sq_digits (num,n+1)

def Ishappy( num ):
    if sum_sq_digits (num) == 1 :
        print("Happy number ")

    elif len(num) == 1 :
        print("Not happy number ")
        
    else :
        num = str( sum_sq_digits (num) )
        Ishappy( num )

              
num = input("Enter a number : ")
Ishappy( num )

Output :-

Enter a number : 100
Happy number
>>>

Enter a number : 64
Not happy number
>>> 

Enter a number : 68
Happy number
>>> 

Enter a number : 28
Happy number
>>>

Enter a number : 40
Not happy number
>>>