Question

How to check if a number is neon number in C#

Answer 1

// Neon Number is a number whose sum of digits of its square is equal to the original number
// 9 : 9 * 9 = 81 : 8 + 1 = 9 : 9 is a neon number

using System;

class Program
{
    static void Main() {
        int num = 9;
        int sqr = num * num; 
        int sumOfDigit = 0;
  
        while (sqr > 0) {
            sumOfDigit += sqr % 10;
            sqr /= 10;
        }
         
        if (num == sumOfDigit)
            Console.Write("Neon Number");
        else
            Console.Write("Not a Neon Number");
    }
}




/*
run:
 
Neon Number
 
*/

 

70+ SQL courses for beginners and professionals