C PROGRAMMING PROGRAM • LOOPS & NUMBER PROBLEMS

Check Whether a Number Is Neon

Learn how to check whether a number is neon using a clear C program.

BeginnerSquareDigit sumNeon number

PROBLEM UNDERSTANDING

Input and expected output

Sample input
9
Sample output
Neon number

COMPLETE C PROGRAM

Complete C implementation

neon-number.c
Open in compiler
#include <stdio.h>

int main(void)
{
    int number, square, sum = 0;

    printf("Enter a non-negative integer: ");
    scanf("%d", &number);
    if (number < 0) {
        printf("Use a non-negative integer.\n");
        return 0;
    }
    square = number * number;
    do {
        sum += square % 10;
        square /= 10;
    } while (square > 0);
    printf(sum == number ? "Neon number\n" : "Not a neon number\n");
    return 0;
}

GUIDED CODE TOUR • NOT LIVE EXECUTION

Study the program line by line

Use the real compiler button above to run and debug with different inputs.

CURRENT STEP

Select Start to walk through the important lines.

SELECTED LINE

No line selected

EXPECTED OUTPUT FOR THE SAMPLE

Neon number
0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

  1. Read the required input values.
  2. Square the number, sum the square's digits and compare that sum with the original.
  3. Display the computed result.

Square the number, sum the square's digits and compare that sum with the original.

EFFICIENCY

Time and space complexity

Time complexity

O(d)

Auxiliary space

O(1)

DEBUGGING CHECKLIST

Common mistakes

Check this

Use the correct format specifier for every variable.

Check this

Initialize variables before using their values.

Check this

Check braces, semicolons and input order carefully.

Try it yourself

Practice: Run the program with the sample input, predict its output, and then test one boundary case of your own.