Count duplicates(Hashing)

 Count duplicates(Hashing)

Problem Statement

Given an array of N elements, your task is to find the count of repeated elements. Print the repeated elements in ascending order along with their frequency.
Have a look at the example for more understanding.

import java.io.*; // for handling input/output

import java.util.*; // contains Collections framework

// don't change the name of this class

// you can add inner classes if needed

class Main {

    public static void main (String[] args) {

           

        // Your code here

        Scanner inputTaker = new Scanner(System.in);

        int n = inputTaker.nextInt();

        int[] arr = new int[n];

        for (int i = 0; i < n; i++) {

            arr[i] = inputTaker.nextInt();

        }

        HashMap<Integer, Integer> map = new HashMap<>();

        for (int i = 0; i < n; i++) {

            if (map.containsKey(arr[i])) {

                Integer prevCount = map.get(arr[i]);

                map.put(arr[i], prevCount + 1);

            } else {

                map.put(arr[i], 1);

            }

        }

        for (Integer number : map.keySet()) {

            if (map.get(number) > 1) {

                System.out.println(number + " " + map.get(number));

            }

        }

    }

}

Count duplicates

Count duplicates

Problem Statement

Given an array of N elements, your task is to find the count of repeated elements. Print the repeated elements in ascending order along with their frequency.
Have a look at the example for more understanding.

import java.util.Arrays;

import java.io.*; // for handling input/output

import java.util.*; // contains Collections framework

 

public class Main {

    // Function to display the repeated elements and their frequencies 

    static void displayOutput(int[] a){

        int i,j,frequency;

        for(i=0; i<a.length; i++){

            frequency = 1;

            for(j=i+1; j<a.length; j++){

                if(a[j] == a[i]){

                    frequency++;

                }

                else{

                    break;

                }

            }

            i=j-1;

            if(frequency > 1){

                System.out.println(a[i] 

                                   + " " + frequency);

            }

        }

    }

    public static void main (String[] args) {

        Scanner sc=new Scanner(System.in);

      int N = sc.nextInt();

         

            

        int []a = new int[N];

        for(int i =0; i<N; i++){

        

          a[i] = sc.nextInt();

                 }

                

            

        

        Arrays.sort(a);

        displayOutput(a);

    }

}