# Neon Number

A neon number is a number where the sum of digits of square of the number is equal to the number. The task is to check and print neon numbers in a range.

Examples:

```Input : 9
Output : Neon Number
Explanation: square is 9*9 = 81 and
sum of the digits of the square is 9.

Input :12
Output : Not a Neon Number
Explanation: square is 12*12 = 144 and
sum of the digits of the square is 9 (1
+ 4 + 4) which is not equal to 12.
```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

The implementation is simple, we first compute square of given number, the find sum of digits in the square.

## C++

 `// C/C++ program to check and print ` `// Neon Numbers upto 10000 ` `#include ` `using` `namespace` `std; ` `#include ` ` `  `int` `checkNeon(``int` `x) ` `{ ` `    ``// storing the square of x ` `    ``int` `sq = x * x; ` ` `  `    ``// calculating the sum of sum of digits ` `    ``// of sq ` `    ``int` `sum_digits = 0; ` `    ``while` `(sq != 0) { ` `        ``sum_digits = sum_digits + sq % 10; ` `        ``sq = sq / 10; ` `    ``} ` `    ``return` `(sum_digits == x); ` `} ` ` `  `// Driver Code ` `int` `main(``void``) ` `{ ` `    ``// Printing Neon Numbers upto 10000 ` `    ``for` `(``int` `i = 1; i <= 10000; i++)  ` `        ``if` `(checkNeon(i)) ` `            ``cout << i << ``" "``;     ` `} `

## Java

 `// Java program to check and print ` `// Neon Numbers upto 10000 ` `import` `java.io.*; ` ` `  `class` `GFG { ` `    ``// function to check Neon Number ` `    ``static` `boolean` `checkNeon(``int` `x) ` `    ``{ ` `        ``// storing the square of x ` `        ``int` `sq = x * x; ` ` `  `        ``// calculating the sum of sum of digits ` `        ``// of sq ` `        ``int` `sum_digits = ``0``; ` `        ``while` `(sq != ``0``) { ` `            ``sum_digits = sum_digits + sq % ``10``; ` `            ``sq = sq / ``10``; ` `        ``} ` `        ``return` `(sum_digits == x); ` `    ``} ` ` `  `    ``// Driver Code ` `    ``public` `static` `void` `main(String args[]) ` `                        ``throws` `IOException ` `    ``{ ` `        ``// Printing Neon Numbers upto 10000 ` `        ``for` `(``int` `i = ``1``; i <= ``10000``; i++)  ` `            ``if` `(checkNeon(i)) ` `                ``System.out.print(i + ``" "``);         ` `    ``} ` `} ` `// This code is contributed by Nikita Tiwari. `

## Python

 `# Python program to check and print  ` `# Neon Numbers upto 10000 ` ` `  `# function to check Neon Number ` `def` `checkNeon (x) : ` `    ``# storing the square of x ` `    ``sq ``=` `x ``*` `x ` `     `  `    ``# calculating the sum of sum of digits ` `    ``# of sq ` `    ``sum_digits ``=` `0` `    ``while` `(sq !``=` `0``) : ` `        ``sum_digits ``=` `sum_digits ``+` `sq ``%` `10` `        ``sq ``=` `sq ``/` `10` `     `  `    ``return` `(sum_digits ``=``=` `x) ` ` `  `# Driver Code ` ` `  `i ``=` `1` `# Printing Neon Numbers upto 10000 ` `while` `i <``=` `10000` `: ` `    ``if` `(checkNeon(i)) : ` `        ``print` `i, ` `    ``i ``=` `i ``+` `1` ` `  `# This code is contributed by Nikita Tiwari. `

## C#

 `// C# program to check and print ` `// Neon Numbers upto 10000 ` `using` `System; ` ` `  `class` `GFG  ` `{ ` `    ``// function to check Neon Number ` `    ``static` `bool` `checkNeon(``int` `x) ` `    ``{ ` `        ``// storing the square of x ` `        ``int` `sq = x * x; ` ` `  `        ``// calculating the sum of sum of digits ` `        ``// of sq ` `        ``int` `sum_digits = 0; ` `        ``while` `(sq != 0)  ` `        ``{ ` `            ``sum_digits = sum_digits + sq % 10; ` `            ``sq = sq / 10; ` `        ``} ` `        ``return` `(sum_digits == x); ` `    ``} ` ` `  `    ``// Driver Code ` `    ``public` `static` `void` `Main() ` `                         `  `    ``{ ` `        ``// Printing Neon Numbers upto 10000 ` `        ``for` `(``int` `i = 1; i <= 10000; i++)  ` `            ``if` `(checkNeon(i)) ` `                ``Console.Write(i + ``" "``);  ` `    ``} ` `} ` ` `  `// This code is contributed by vt_m. `

## PHP

 ` `

Output:

```1 9
```

This article is contributed by Nikita Tiwari. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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