7. K largest elements.cpp

// Link: http://bit.ly/41BAKo6 

// Code
class Solution
{
    public:
    //Function to return k largest elements from an array.
    vector<int> kLargest(int arr[], int n, int k)
    {
        // code here
        // The smallest element is always at the top of min heap.
        priority_queue<int, vector<int>, greater<int>> pq;
        for(int i=0;i<n;i++){
            pq.push(arr[i]);
            if(pq.size()>k) pq.pop();
        }
        vector<int> ans;
        while(!pq.empty()){
            ans.push_back(pq.top());
            pq.pop();
        }
        reverse(ans.begin(), ans.end());
        return ans;
    }
};


/*
Time complexity: O(nlogk)
Space complexity: O(k)
*/


// Code by Shumbul Arifa - https://linktr.ee/shumbul