排序之前 K 个高频元素

每日一题ing，今天是个medium题347. Top K Frequent Elements

class Solution {
public:
    vector topKFrequent(vector& nums, int k) {
        unordered_map umap;
        for(int i=0;i> pq;
        for(auto p:umap){
            pq.push(pair(-p.second,p.first));
            if(pq.size()>k){
                pq.pop();
            }
        }
        vector ret;
        for(int i=0;i