import java.util.Arrays;

import java.util.Scanner;

public class arrayfreq {

public static void main(String args[])

{

Scanner sc=new Scanner(System.in);

System.out.println("enter the size of array");

int n =sc.nextInt();

int arr[]=new int[n];

int dup[]=new int[n];

for(int i=0;i<n;i++)

{

arr[i]=sc.nextInt();

dup[i]=-1;

}

for(int i=0;i<arr.length;i++)

{

int count=1;

for(int j=i+1;j<arr.length;j++)

{

if(arr[i]==arr[j])

{

count++;

//eg 1 2 1 array hai toh vo ek baar 1 ko 2 baar count krega,2 ko 1 baar,aur 1 v dubara1 count krega....

//aisa naa krne ke liye we write next statement

dup[j]=0;

}

}

//ek Element array mein kitni baar aarha.

if(dup[i]!=0)

{

dup[i]=count;

}

}

System.out.println("frequency of each elelemnt is");

for(int i=0;i<n;i++)

{

if(dup[i]!=0)

{

System.out.println(arr[i]+" comes "+dup[i]+" times");

}

}

// method 2

int max = arr[0];

System.out.println("2nd method");

for (int i = 1; i < arr.length; i++)

{

if (arr[i] > max)

max = arr[i];

}

int temp[]=new int[max+1];

for(int j=0;j<n;j++)

{

temp[arr[j]]++;

}

for(int i=0;i<n;i++)

{

if(temp[arr[i]]>0)

{

System.out.println(arr[i]+" comes "+temp[arr[i]]+" times");

temp[arr[i]]=0;

}

}

//method 3 hashmap

System.out.println("3rd method");

java.util.HashMap<Integer,Integer> h=new java.util.HashMap<>();

for(int i=0;i<n;i++)

{

if(h.containsKey(arr[i]))

{

h.put(arr[i],h.get(arr[i])+1);

}

else

{

h.put(arr[i],1);

}

}

for (int i : h.keySet()) {

System.out.println("key: " + i + " value: " + h.get(i));

}

}

}