k largest or smallest elements in an array

 Question- write an efficient program to print k largest elements in an array. Elements in array can be in any order. 

Method- Sort array in descending order, print first k elements 

code-

#include<bits/stdc++.h>

using namespace std;

void kelements(int arr[], int n, int k)

{

    sort( arr, arr + n, greater<int>());

    for(int i = 0 ; i < k ; i ++)

    {

            cout<<arr[i]<<" ";

    }


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