Leetcode 215 Kth Largest Element in an Array

1. Description of the problem

Find out the number of K-large in the array, note that the array is an unordered array.
　　

2. Methods and Ideas

is a classic algorithm problem. The solution also has several kinds, one is to sort first, then take out the number of k large, because the sorting algorithm the quickest efficiency is o(nlOgn) , so overall efficiency is o(nlOgn) 。 The second is to use the priority queue, the usage of priority queue in SLT, the internal is implemented in the way of heap. Time efficiency is also relatively high, o(nlOgn) 。
　　

class Solution {public:    int findKthLargest(vector<int>int k) {        priority_queue<int> pq;        for(auto &num:nums)        {            pq.push(num);        }        for(;k>1;k--) pq.pop();        return pq.top();    }};

Leetcode 215 Kth Largest Element in an Array