692. 前K个高频单词 - 力扣（LeetCode）

//#include<set>
class Solution {
public://仿函数struct compare{bool operator()(const pair<string,int>& kv1,const pair<string,int>& kv2){return kv1.second > kv2.second;}};vector<string> topKFrequent(vector<string>& words, int k) {//插入（在插入过程中，已经按照字典序排好序了）map<string,int> count_map;for(auto e : words){count_map[e]++;}//排序vector<pair<string,int>> v(count_map.begin(),count_map.end()); stable_sort(v.begin(),v.end(),compare());//拿到前K个vector<string> ret;for(int i = 0; i<k; ++i){ret.push_back(v[i].first);}return ret;}
};

单词识别_牛客题霸_牛客网 (nowcoder.com)

#include <algorithm>
#include <cctype>
#include <iostream>
#include<map>
#include<string>
#include<vector>
#include <sstream>using namespace std;struct compare
{bool operator()(const pair<string,int>& kv1 ,const pair<string,int>& kv2){return kv1.second > kv2.second;}
};int main() {string s;getline(std::cin,s,'.');//变小字母for(auto& c : s){c = tolower(c);}map<string,int> count_map;istringstream iss(s);string word;//插入单词并计数while(iss >> word){count_map[word]++;}//放入vecotrvector<pair<string,int>> v(count_map.begin(),count_map.end());   //按照统计次数进行降序stable_sort(v.begin(), v.end(),compare());//输出for(auto e : v){cout<<e.first<<":"<<e.second<<endl;}return 0;
}
// 64 位输出请用 printf("%lld")