215. Kth Largest Element in an Array

https://leetcode.com/problems/kth-largest-element-in-an-array/

Problem

Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element.

Example 1:

Input: [3,2,1,5,6,4] and k = 2
Output: 5

Example 2:

Input: [3,2,3,1,2,4,5,5,6] and k = 4
Output: 4

Note: You may assume k is always valid, 1 ≤ k ≤ array's length.

Solution

class Solution {
public:
    int findKthLargest(vector<int>& nums, int k) {
        priority_queue<int, vector<int>, greater<int>> min_heap;
        for (const auto &n: nums) {
            if (min_heap.size() < k) {
                min_heap.push(n); continue;
            }
            
            if (min_heap.top() < n) {
                min_heap.pop(); min_heap.push(n);
            }
        }
        return min_heap.top();
    }
};