Dupledrome Checking

Code to Check Whether the entered String is Dupledrome or Not.

Dupledrome means that every element present in the String should be present twice i.e., "rattar" is a dupledrome string whereas "rasrat" is not a Dupledrome String.

import java.util.Scanner; //Scanner Class
public class DupledromeChecking {
    static boolean isDupledrome(String ap)
    {
        int N = ap.length();
        char[] ar = new char[N]; //Char Array
        ar = ap.toCharArray();
        int i,k=0,q=0,r=0,j;
        for(i=0;i<N;i++)
        {
            for(j=0;j<N;j++)
            {
                if(ar[i]==ar[j]) //When Values are Equal
                {
                    r++; //Increment The Count
                }
            }
        }
        /*If The Counted Value is Equal to Twice the Lenght 
        then it is Said that every element present 
        exactly twice */
        if(r==(N*2))
        {
            return true;
        }
        else
        {
            return false;
        }
    }
    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in); //Scanner Object
        System.out.println("Program to Check Whether the Entered String is Dupledrome or Not");
        System.out.print("Enter the String:- \t");
        String s1 = sc.next();
        boolean result = isDupledrome(s1); //Calling Function
        System.out.println("Dupledrome String:- \t"+result);
    }
}