# C Program to Check Neon Number

C program to check neon number; Through this tutorial, we will learn how to check neon number in c program using for loop, while loop and function.

Let’s use the following algorithm to write a program to check whether a number is neon or not; as follows:

• Take the number as input from the user
• Find the square of the number
• Find the sum of the digits in the square
• Compare the sum with the number. If both are equal then it is a Neon number

## Programs to Check Neon Number

• C Program to Check Neon Number using For Loop
• C Program to Check Neon Number using While Loop
• C Program to Check Neon Number using Function

### C Program to Check Neon Number using For Loop

```#include <stdio.h>

int main()
{
int i, num, square, sumDigits = 0;

printf("Enter a number: ");
scanf("%d", &num);

square = num * num;

for(i = 0; i<=square; i++)
{
sumDigits += square % 10;
square /= 10;
}

if (num == sumDigits)
{
printf("It is a Neon number\n");
}
else
{
printf("It is not a Neon number\n");
}

return 0;
}```

The output of the above c program; as follows:

```Enter a number: 10
It is not a Neon number```

### C Program to Check Neon Number using While Loop

```#include <stdio.h>

int main()
{
int num, square, sumDigits = 0;

printf("Enter a number: ");
scanf("%d", &num);

square = num * num;

while (square != 0)
{
sumDigits += square % 10;
square /= 10;
}

if (num == sumDigits)
{
printf("It is a Neon number\n");
}
else
{
printf("It is not a Neon number\n");
}

return 0;
}```

The output of the above c program; as follows:

```Enter a number: 9
It is a Neon number```

### C Program to Check Neon Number using Function

```#include <stdio.h>

int isNeon(int num)
{
int square, sumDigits = 0;
square = num * num;

while (square != 0)
{
sumDigits += square % 10;
square /= 10;
}

if (num == sumDigits)
{
printf("It is a Neon number\n");
}
else
{
printf("It is not a Neon number\n");
}
}

int main()
{
int n;

printf("Enter a number: ");
scanf("%d", &n);

isNeon(n);

return 0;
}```

The output of the above c program; as follows:

```Enter a number: 1
It is a Neon number```