P044.c

Metadata

• Author — Amit Dutta
• Last updated — 12 Dec 2025
• License — MIT License (See the LICENSE file for details)

Problem Statement

Problem Statement

Write a program to input a number and check whether the number is Pronic number or not. Pronic Number: The number which is the product of two numbers which is the product of two consecutive integer. Ex: 20 = 4 * 5

Source Code

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

int main()
{
    int num, iterationIndex;
    bool isPronic = false;
    printf("Enter the number : ");
    if (scanf("%d", &num) != 1)
    {
        printf("\nYou have to enter a number, not an character or symbol.");
        return 1;
    }
    if (num < 1)
    {
        printf("\nOnly postive number is allowed.");
        return 1;
    }
    for (iterationIndex = 1; iterationIndex <= num / 2; iterationIndex++)
    {
        if (iterationIndex * (iterationIndex + 1) == num)
        {
            printf("\nInput %d is a Pronic Number.", num);
            isPronic = true;
            break;
        }
    }
    if(!isPronic)
    {
        printf("\nInput %d is not a Pronic Number.", num);
    }
    return 0;
}
*/

// using direct return method (more efficient and generally preferred)...

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

int main()
{
    int num, iterationIndex, iterationLimit;
    printf("Enter the number : ");
    if (scanf("%d", &num) != 1)
    {
        printf("\nYou have to enter a number, not an character or symbol.");
        return 1;
    }
    if (num < 1)
    {
        printf("\nOnly postive number is allowed.");
        return 1;
    }
    iterationLimit = (int)sqrt(num);
    for (iterationIndex = 1; iterationIndex <= iterationLimit; iterationIndex++)
    {
        if (iterationIndex * (iterationIndex + 1) == num)
        {
            printf("\nInput %d is a Pronic Number.", num);
            return 0;
        }
    }
    printf("\nInput %d is not a Pronic Number.", num);
    return 0;
}