692. 前K个高频单词 

 1 class Solution 
 2 {
 3 struct cmp
 4 {
 5     bool operator()(pair<string,int> const &left,pair<string,int> const &right)
 6     {
 7         if(left.second == right.second) return left.first > right.first;
 8         return left.second < right.second;
 9     }
10 };
11 
12 public:
13     vector<string> topKFrequent(vector<string>& words, int k) 
14     {
15         priority_queue<pair<string,int>,vector<pair<string,int>>,cmp> pq;
16         unordered_map<string,int> hash;
17         for(auto a : words) hash[a] ++;
18         for(auto a : hash) pq.push({a.first,a.second});
19 
20         vector<string> ans;
21         while(k --)
22         {
23             ans.push_back(pq.top().first);
24             pq.pop();
25         }
26         return ans;
27     }
28 };

 

posted @ 2020-04-09 22:21  Jinxiaobo0509  阅读(154)  评论(0)    收藏  举报