diff --git a/main.cpp b/main.cpp
index f4ecab8..f0e25fc 100644
--- a/main.cpp
+++ b/main.cpp
@@ -6,6 +6,11 @@
 #include <string>
 #include <thread>
 #include <map>
+#include <utility>
+#include <shared_mutex>
+#include <chrono>
+#include <mutex>
+#include <future>
 
 
 struct User {
@@ -15,12 +20,16 @@ struct User {
 };
 
 std::map<std::string, User> users;
-std::map<std::string, long> has_login;  // 换成 std::chrono::seconds 之类的
+std::map<std::string, decltype(std::chrono::steady_clock::now())> has_login;  // 换成 std::chrono::seconds 之类的
+std::shared_mutex sm;
+std::shared_mutex sm_login;
 
 // 作业要求1：把这些函数变成多线程安全的
 // 提示：能正确利用 shared_mutex 加分，用 lock_guard 系列加分
 std::string do_register(std::string username, std::string password, std::string school, std::string phone) {
-    User user = {password, school, phone};
+    User user = {std::move(password), std::move(school), std::move(phone)};
+
+    std::unique_lock grd(sm);
     if (users.emplace(username, user).second)
         return "注册成功";
     else
@@ -29,13 +38,31 @@ std::string do_register(std::string username, std::string password, std::string
 
 std::string do_login(std::string username, std::string password) {
     // 作业要求2：把这个登录计时器改成基于 chrono 的
-    long now = time(NULL);   // C 语言当前时间
+//    long now = time(NULL);   // C 语言当前时间
+//    if (has_login.find(username) != has_login.end()) {
+//        int sec = now - has_login.at(username);  // C 语言算时间差
+//        return std::to_string(sec) + "秒内登录过";
+//    }
+//    has_login[username] = now;
+
+    std::shared_lock grd_log_sl(sm_login);
+//    auto find=;
+
+    auto now=std::chrono::steady_clock::now();
     if (has_login.find(username) != has_login.end()) {
-        int sec = now - has_login.at(username);  // C 语言算时间差
-        return std::to_string(sec) + "秒内登录过";
+        auto sec=now-has_login.at(username);
+
+        using double_s=std::chrono::duration<double>;
+        double s=std::chrono::duration_cast<double_s>(sec).count();
+        return std::to_string(s) + "秒内登录过";
     }
+    grd_log_sl.unlock();
+
+    std::unique_lock grd_log(sm_login);
     has_login[username] = now;
+    grd_log.unlock();
 
+    std::shared_lock grd(sm);
     if (users.find(username) == users.end())
         return "用户名错误";
     if (users.at(username).password != password)
@@ -44,11 +71,19 @@ std::string do_login(std::string username, std::string password) {
 }
 
 std::string do_queryuser(std::string username) {
-    auto &user = users.at(username);
     std::stringstream ss;
-    ss << "用户名: " << username << std::endl;
-    ss << "学校:" << user.school << std::endl;
-    ss << "电话: " << user.phone << std::endl;
+    try {
+        std::shared_lock grd(sm);
+        auto &user = users.at(username);
+        grd.unlock();
+        ss << "用户名: " << username << std::endl;
+        ss << "学校:" << user.school << std::endl;
+        ss << "电话: " << user.phone << std::endl;
+    }
+    catch (...) {
+        std::cout<<"username: "<<username<<"not found! "<<'\n';
+    }
+
     return ss.str();
 }
 
@@ -57,8 +92,10 @@ struct ThreadPool {
     void create(std::function<void()> start) {
         // 作业要求3：如何让这个线程保持在后台执行不要退出？
         // 提示：改成 async 和 future 且用法正确也可以加分
-        std::thread thr(start);
+//        std::thread thr(start);
+        fts.push_back(std::async(start));
     }
+    std::vector<std::future<void>> fts;
 };
 
 ThreadPool tpool;
@@ -85,5 +122,8 @@ int main() {
     }
 
     // 作业要求4：等待 tpool 中所有线程都结束后再退出
+    for (auto &ret:tpool.fts) {
+            ret.wait();
+    }
     return 0;
 }