class Solution {

public:

    int findKthLargest(vector<int>& nums, int k) {

        priority_queue<int,vector<int>,greater<int> >q;//小顶堆

        //priority_queue<int,vector<int>,less<int> >q;大顶堆

        int len=nums.size();

        for(int i=;i<len;i++){

            if(i<k)

                q.push(nums[i]);

            else{

                if(q.top()<nums[i]){

                    q.pop();

                    q.push(nums[i]);

                }

            }

        }

        return q.top();

    }

};

/**

建立一个小顶堆，每次出现新元素大于堆顶元素则替换堆顶元素

**/

class Solution {

public:

    int findKthLargest(vector<int>& nums, int k) {

        vector<int> topk;

        struct cmp{

            bool operator()(int a,int b){return a>b;}//小顶堆

        };

        priority_queue<int,vector<int>,cmp> q;

        for(int num:nums){

            if(q.size()<k){

                q.push(num);continue;

            }

            if(num>q.top()){

                q.pop();q.push(num);

            }

        }

        return q.top();

    }

};