// main.cpp #include <algorithm> #include <chrono> #include <ctime> #include <fstream> #include <iomanip> #include <iostream> #include <map> #include <mutex> #include <queue> #include <sstream> #include <thread> #include <uuid/uuid.h> #include <vector> std::string get_time_now() { std::chrono::time_point<std::chrono::high_resolution_clock> now = std::chrono::high_resolution_clock::now(); time_t raw_time = std::chrono::high_resolution_clock::to_time_t(now); struct tm tm_info = *localtime(&raw_time); auto seconds = std::chrono::duration_cast<std::chrono::seconds>(now.time_since_epoch()); auto mills = std::chrono::duration_cast<std::chrono::milliseconds>(now.time_since_epoch()); auto micros = std::chrono::duration_cast<std::chrono::microseconds>(now.time_since_epoch()); auto nanos = std::chrono::duration_cast<std::chrono::nanoseconds>(now.time_since_epoch()); std::stringstream ss; ss << std::put_time(&tm_info, "%Y%m%d%H%M%S") << "_" << std::setw(3) << std::setfill('0') << (mills.count() - seconds.count() * 1000) << std::setw(3) << std::setfill('0') << (micros.count() - mills.count() * 1000) << std::setw(3) << std::setfill('0') << (nanos.count() - micros.count() * 1000); return ss.str(); } char *uuid_value = (char *)malloc(40); char *get_uuid_value() { uuid_t new_uuid; uuid_generate(new_uuid); uuid_unparse(new_uuid, uuid_value); return uuid_value; } void map_erase(const int &len,const int&length) { std::map<int,std::string> _mp; for(int i=0;i<len;i++) { _mp.insert(std::pair<int,std::string>(i+1,get_uuid_value())); } std::cout<<"Map size:"<<_mp.size()<<std::endl; auto start=_mp.begin(); std::map<int,std::string>::iterator itr=_mp.begin(); for(int i=0;i<10;i++) { ++itr; } _mp.erase(start,itr); std::cout<<"Map size:"<<_mp.size()<<std::endl; } int main(int args, char **argv) { map_erase(atoi(argv[1]),atoi(argv[2])); std::cout << get_time_now() << ",thread id:" << std::this_thread::get_id() << ",in " << __FUNCTION__ << std::endl; }
g++-12 -std=c++2a -I. *.cpp -o h1 -luuid -lpthread
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