Write a Program in Java to input a number and check whether it is a Pronic Number or Heteromecic Number or not.

Pronic Number : A pronic number, oblong number, rectangular number or heteromecic number, is a number which is the product of two consecutive integers, that is, n (n + 1).

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 … etc.

Code-1: Using Pure Function ( Return):

import java.util.*;

class Pronic_Number

{

public int func ( int n )

{

   int i,f=0;
    for( i=1; i<=n; i++)
    {
      if ( i * ( i + 1 ) ==n )
      {
        f=1;
        break;
      }
    }

return f;

}

public static void main ( String args [ ] )

  {

    int no, p;

    Scanner sc=new Scanner(System.in);

    System.out.println("Enter the number: ");

    no=sc.nextInt();

    Pronic_Number obj = new Pronic_Number( );

    p=obj.func(no);

    if(p==1)
    {
     System.out.println(no + " is a Pronic Number");
    }
      else
        System.out.println(no + " is not a Pronic Number");
  }

}

Output:
Enter a number : 20
  20 is a Pronic Number.

Enter a number : 73
73 is not a Pronic Number.