Program to print Happy Numbers between 1 and 100 in Python. This program contains if else condition statement, for, while loop and print statement. This is for beginners, class 11,12 and B Tech computer science students.

### Program to print Happy Numbers between 1 and 100 in Python

### What is Happy numbers ?

In number theory, a **Happy number** is a number which eventually reaches 1 when replaced by the sum of the square of each digit. For instance, 13 is a happy number because , and . On the other hand, 4 is not a happy number because the sequence starting with and eventually reaches , the number that started the sequence, and so the process continues in an infinite cycle without ever reaching 1. A number which is not happy is called **sad** or **unhappy**.

### Source code :

```
def isHappyNumber(num):
rem = sum = 0;
while(num > 0):
rem = num%10;
sum = sum + (rem*rem);
num = num//10;
return sum;
print("List of happy numbers between 1 and 100: ");
for i in range(1, 101):
result = i;
while(result != 1 and result != 4):
result = isHappyNumber(result);
if(result == 1):
print(i),
print(" "),
```

### Source code Explanation :

**Step 1: isHappyNumber() function will determine whether a number is happy or not**

def isHappyNumber(num):

rem = sum = 0;**Step 2: Calculates the sum of squares of digits** **using while loop**

while(num > 0):

rem = num%10;

sum = sum + (rem*rem);

num = num//10;

return sum;**Step 3:Displays all happy numbers between 1 and 100**

print(“List of happy numbers between 1 and 100: “);

for i in range(1, 101):

result = i;**Step 4:Happy number always ends with 1 and unhappy number ends in a cycle of repeating numbers which contains 4**

while(result != 1 and result != 4):

result = isHappyNumber(result);

if(result == 1):

print(i),

print(” “),

### Output :

List of happy numbers between 1 and 100: 1 7 10 13 19 23 28 31 32 44 49 68 70 79 82 86 91 94 97 100

### Output Explanation :

The List of happy number between 1 and 100 is printed on the screen.

### Conclusion :

The program runs fine.

Thank you for reading, learning and download source code of Program to print Happy Numbers between 1 and 100 in Python. This program contains if else condition statement, for, while loop and print statement. This is for beginners, class 11,12 and B Tech computer science students. for more programs links is given below-

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