C program to Check a Number is a Neon Number

Write a c program to check a number is a neon number or not using the for loop. If the number equals the sum of digits of the square of a number, it is a neon number.

  1. We use the math pow function to find the square of a number.
  2. Divide the output into individual digits and calculate the sum of it.
  3. The if else to check whether the sum of digits in a square equals the actual number. If true, it is a neon number.
#include <stdio.h>
#include<math.h>

int main()
{
  int Number, squr, rem, Sum;
  
  printf("Enter Number to Check = ");
  scanf("%d", &Number);

  squr = pow(Number, 2);

  for (Sum = 0; squr > 0; squr = squr / 10)
  {
    rem = squr % 10;
    Sum = Sum + rem;
  }

  if (Number == Sum)
    printf("\n%d is a Neon Number.\n", Number);
  else
    printf("\n%d is not.\n", Number);
}
C program to Check a Number is a Neon Number

This C program checks whether the given number is a neon number or not using a while loop.

#include <stdio.h>
#include<math.h>

int main()
{
  int Number, squr, rem, Sum = 0;
  
  printf("Enter Number to Check = ");
  scanf("%d", &Number);

  squr = pow(Number, 2);
  printf("The Square of a Number %d = %d\n", Number, squr);

  while(squr > 0)
  {
    rem = squr % 10;
    Sum = Sum + rem;
    squr = squr / 10;
  }
  printf("The Sum of Digits in a Square = %d\n", Sum);
  if (Number == Sum)
    printf("\n%d is a Neon Number.\n", Number);
  else
    printf("\n%d is not.\n", Number);
}
Enter Number to Check = 9
The Square of a Number 9 = 81
The Sum of Digits in a Square = 9

9 is a Neon Number.

In this check neon number example, the squareDigitsSum recursive function divide and find the sum by calling it recursively.

#include <stdio.h>
#include<math.h>

int squareDigitsSum(int num)
{
  static int rem, sum = 0;

  if(num > 0)
  {
    rem = num % 10;
    sum = sum + rem;
    squareDigitsSum(num / 10);
  }
  return sum;
}

int main()
{
  int Number;
  
  printf("Enter Number to Check = ");
  scanf("%d", &Number);

  int squr = pow(Number, 2);

  int Sum = squareDigitsSum(squr);

  printf("The Square of %d Number = %d\n", Number, squr);

  printf("The Sum of Digits in %d = %d\n", squr, Sum);

  if (Number == Sum)
    printf("\n%d is a Neon Number.\n", Number);
  else
    printf("\n%d is not.\n", Number);
}
Enter Number to Check = 5
The Square of 5 Number = 25
The Sum of Digits in 25 = 7

5 is not.

About Suresh

Suresh is the founder of TutorialGateway and a freelance software developer. He specialized in Designing and Developing Windows and Web applications. The experience he gained in Programming and BI integration, and reporting tools translates into this blog. You can find him on Facebook or Twitter.