March 6, 2022, Learn eTutorial

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In this simple python program, we have to check for a happy number. It's a beginner-level python program.

To understand this example, you should have knowledge of the following Python programming topics:

In this python program example, we need to check for a happy number. **A number is said to be a Happy Number if the sum of the squares of all the digits in that number yield one when it is repeatedly doing**. If that results in endless cycles of resultant 4, then that number is said to be an unhappy number. Let us take an example to check if a number is a happy number or not to understand clearly.

Take number 32. Now, let's split the number and check for a Happy number or an unhappy number.

**3**, We split the number and take the sum of squares of the digits in that number^{2}+ 2^{2}= 13**1**, again split the resultant number 13 and take the sum of the squares of 1 and 3^{2}+ 3^{2}= 10**1**, again we split the number 10 and take the sum of the square of each digit^{2}+ 0^{2}= 1- the
**result is 1**, so the given number**32 is Happy number**

We also have a program to display happy numbers between the range 1 and 100 in our python program collection.

To solve this python program, we apply the logic using a `while loop`

in python until the result from the user-defined function is 1 or 4. Use a user-defined function in python where we pass the number from the main program to the function then we initialize two variables for remainder and sum as zero. Then check for a happy number by starting a `while loop`

** **where the number is greater than zero.

Take the remainder of the number by using the **mod **operator by 10, and we add the **sum **with the square of the remainder. Then we divide the number by 10 to split the number and take the next digit. Finally, we return **sum** as a result. Then check the result is 1, using `if condition`

in python. If so `print`

the number is a happy number. else unhappy number.

**STEP 1:** Predefine a number to check for a happy number. We can use the input function also to receive input from the user.

**STEP 2:** Initialize the variable for storing the result of the python program.

**STEP 3:** Open a `while loop`

until the result is 1 or 4, and call the user-defined function for checking the number is a happy number or not in the python programming language. We pass the number as a parameter to the function.

**STEP 1:** Initialize the variables **rem** and **sum ** as zero.

**STEP 2:** Open a `while loop`

until the **num** is equal to zero.

**STEP 3:** We take the remainder using the **mod **operator.

**STEP 4:** Sum is getting added to the sum with the square of the remainder.

**STEP 5:** Split the number by dividing the **num** by 10 and return the **sum**.

` ````
def isHNumber(num):
rem = sum = 0
while(num > 0):
rem = num
sum = sum + (rem*rem)
num = num//10
return sum;
num = 86
result = num
while(result != 1 and result != 4):
result = isHNumber(result);
print("The number is being checked")
if(result == 1):
print(str(num) + " is a happy number");
elif(result == 4):
print(str(num) + " isn't a happy number");
```

82 is a happy number