Problem: Write a C program to check whether the number is Neon or not.

A number is called a Neon Number if the sum of digits of the square of the number is equal to the original number.

Example: 9

Steps to check neon number in C:

1. Input a number.
2. Calculate the square of the number.
3. Sum digits of the square.
4. Check whether the calculated sum is equal to the original number.
5. If yes then the number is Neon, else it is not.

Here is the implementation of the steps in C:

``````#include <stdio.h>

int main()
{
int num, digit, sum =0;

//Input a number
printf("Enter a number to check for neon number: \n");
scanf("%d",&num);

//Calculate square of the input
int square = num*num;

//Sum the digits of the square
while(square!=0){
digit = square%10;
sum += digit;
square = square/10;
}

//Check if sum is equal to the input number
if(sum == num)
printf("Neon Number \n");
else
printf("Not a Neon Number \n");

return 0;
}``````

Output:

Enter a number to check for neon number:
9
Neon Number

To sum up the digits of the square, we have individually extracted each digit using the Modulus operator (i.e. `square%10`) and added it to the `sum` variable.

In the end, we compared the calculated `sum` with the input number `num` to check whether the given number is a Neon number or not.

### This Post Has One Comment

1. Anshuman

I appreciate your work