Check if a given number is Pronic

Difficulty Level : Easy
Last Updated : 15 May, 2018

The numbers that can be arranged to form a rectangle are called Rectangular Numbers (also known as Pronic numbers). The first few Pronic numbers are:
0, 2, 6, 12, 20, 30, 42, 56, 72, 90, 110, 132, 156, 182, 210, 240, 272, 306, 342, 380, 420, 462 . . . . . .

Pronic number is a number which is the product of two consecutive integers, that is, a number n is a product of x and (x+1). The task is to check and print Pronic Numbers in a range.

Examples :

Input  : 6
Output : Pronic Number
Explanation: 6 = 2 * 3 i.e 6 is a product
of two consecutive integers 2 and 3.

Input :56
Output :Pronic Number
Explanation: 56 = 7 * 8 i.e 56 is a product 
of two consecutive integers 7 and 8. 

Input  : 8
Output : Not a Pronic Number
Explanation: 8 = 2 * 4 i.e 8 is a product of 
2 and 4 which are not consecutive integers.

C/C++

// C/C++ program to check  
// if a number is pronic 
#include <iostream> 
#include <math.h> 
  
using namespace std; 
  
// function to check  
// Pronic Number 
bool checkPronic(int x) 
{ 
  
    for (int i = 0;  
             i <= (int)(sqrt(x));  
             i++) 
  
        // Checking Pronic Number  
        // by multiplying consecutive 
        // numbers 
        if (x == i * (i + 1))  
        return true; 
  
    return false; 
} 
  
// Driver Code 
int main(void) 
{ 
    // Printing Pronic Numbers 
    // upto 200 
    for (int i = 0; i <= 200; i++)  
        if (checkPronic(i)) 
            cout << i << " "; 
      
    return 0; 
} 
// This code is contributed 
// by Nikita Tiwari. 

Java

// Java program to check and 
// Print Pronic Number upto 200 
import java.io.*; 
import java.util.*; 
import java.math.*; 
  
class GFG  
{ 
  
    // function to check Pronic Number 
    static boolean checkPronic(int x) 
    { 
        for (int i = 0;  
             i <= (int)(Math.sqrt(x));  
             i++)  
              
            // Checking Pronic Number  
            // by multiplying consecutive 
            // numbers 
            if (x == i * (i + 1))  
                return true; 
          
        return false; 
    } 
  
    // Driver Code 
    public static void main(String[] args) 
    { 
        // Printing Pronic  
        // Numbers upto 200 
        for (int i = 0; i <= 200; i++)  
            if (checkPronic(i)) 
                System.out.print(i + " ");      
    } 
} 
  
// This code is contributed  
// by Nikita Tiwari 

Python

# Python program to check  
# and print Pronic Numbers  
# upto 200 
import math 
  
# function to check  
# Pronic Number 
def checkPronic (x) : 
  
    i = 0
    while ( i <= (int)(math.sqrt(x)) ) : 
          
        # Checking Pronic Number  
        # by multiplying consecutive  
        # numbers 
        if ( x == i * (i + 1)) : 
            return True
        i = i + 1
  
    return False
  
# Driver Code 
  
# Printing Pronic 
# Numbers upto 200 
i = 0
while (i <= 200 ) : 
    if checkPronic(i) : 
        print i, 
    i = i + 1
  
# This code is contributed  
# by Nikita Tiwari. 

C#

// Java program to check and 
// Print Pronic Number upto 200 
using System; 
  
class GFG 
{ 
  
    // function to check 
    // Pronic Number 
    static bool checkPronic(int x) 
    { 
        for (int i = 0;  
                 i <= (int)(Math.Sqrt(x));  
                 i++)  
              
            // Checking Pronic Number by  
            // multiplying consecutive numbers 
            if (x == i * (i + 1))  
                return true; 
          
        return false; 
    } 
  
    // Driver Code 
    public static void Main() 
    { 
        // Printing Pronic  
        // Numbers upto 200 
        for (int i = 0; i <= 200; i++)  
            if (checkPronic(i)) 
                Console.Write(i + " ");  
    } 
} 
  
// This code is contributed by vt_m. 

PHP

<?php 
// PHP program to check  
// if a number is pronic 
  
// function to check  
// Pronic Number 
function checkPronic($x) 
{ 
  
    for ($i = 0;  
         $i <= (sqrt($x));  
         $i++) 
  
        // Checking Pronic Number  
        // by multiplying consecutive 
        // numbers 
        if ($x == $i * ($i + 1))  
        return true; 
  
    return false; 
} 
  
// Driver Code 
  
// Printing Pronic 
// Numbers upto 200 
for ($i = 0; $i <= 200; $i++)  
    if (checkPronic($i)) 
        echo $i , " "; 
  
// This code is contributed by Ajit 
?> 

Output :

0 2 6 12 20 30 42 56 72 90 110 132 156 182

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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