k largest elements

Given an array Arr of N positive integers, find K largest elements from the array. The output elements should be printed in decreasing order.

• Time : O(nlogk)
• Space : O(k)

class Solution{
public:
    vector<int> kLargest(int arr[], int n, int k) {
        priority_queue<int, vector<int>, greater<int>> pq;
        for(int i = 0; i < n; i++) {
            pq.push(arr[i]);
            while(pq.size() > k) pq.pop();
        }
        vector<int> res(pq.size());
        while(!pq.empty()) {
            res[pq.size() - 1] = pq.top();
            pq.pop();
        }
        return res;
    }
};