java programming problem

program question:

Write a code to find duplicate elements in array and total count of duplicate elements.
eg. arr={5,3,4,6,7,5,3,2,1}
Duplicate elements:- 5,3
Total duplicate count:- 2

solution:


package com.shashi;

import java.util.ArrayList;


public class DuplicateCount {

    public static void main(String []args)
    {
      
        int arr[]={5,3,4,6,7,5,3,2,1,1};
        int count=0;
        ArrayList<Integer> list=new ArrayList<Integer>();
        ArrayList<Integer> dup=new ArrayList<Integer>();
        for(int ar:arr)
        {
            if(!list.contains(ar))
            {
                list.add(ar);
            }
            else
            {
                dup.add(ar);
                count++;
            }
        }
      
        //printing data
        System.out.print("duplicate elements are:"+dup+"\n");
        System.out.print("Number of such elements are:"+count);
      
    }
}

output:

duplicate elements are:[5, 3, 1]
Number of such elements are:3

Explanation:

--I created an arraylist that stores that stores duplicate elements.

logic

move:
if(arraylist element already presented add the element to duplicate)
increase count value
repeat move;