There shouldn't be any memory leak anymore, and it's now super fast.

include/ServerUtils.h

@@ -20,14 +20,14 @@ class ServerUtils {
         static void send_data(int client_fd, const string& data);
         static void send_image(int client_fd, const string& path, image_type type);
         static size_t send_all(int client_fd, const char* data, size_t length);
-        static string get_ip(int client_fd);
+        static uint32_t get_ip_2(int client_fd);
 };
 
 const string HTML_RESPONSE_HEADER = 
         "HTTP/1.1 200 OK\r\n"
         "Content-Type: text/html; charset=utf-8\r\n"
         "Transfer-Encoding: chunked\r\n"
-        //"Cache-control: max-age=12000\r\n"
+        "Cache-control: max-age=12000\r\n"
         "Connection: close\r\n\r\n";
 
 const string CSS_RESPONSE_HEADER = 

include/Track.h

@@ -5,7 +5,7 @@
 using namespace std;
 
 struct Track {
-    string Ip;
+    uint32_t Ip;
     string UserAgent;
 };
 

include/WordUtils.h

@@ -12,6 +12,7 @@ struct WordUtils {
     static unordered_map<string, unordered_map<string, int>> load_data(const string& path);
     static vector<string> load_css(const string& path);
     static vector<string> predict_next_word(const string& input, const unordered_map<string, unordered_map<string, int>>& word_frequencies, size_t count);
+    static vector<string> predict_next_word_2(const string& input, const unordered_map<string, unordered_map<string, int>>& word_frequencies, size_t count);
     static string load_file(const string& path);
     static vector<string> split_string(const string& input, data_type type);
     static string extract_url(const string& input);
@@ -19,6 +20,7 @@ struct WordUtils {
     static bool contains_image(const string& input);
     static string extract_image_name(const string& input);
     static string create_tag(const unordered_map<string, unordered_map<string, int>>& word_frequencies, const char& hash);
+    static string create_tag_2(const unordered_map<string, unordered_map<string, int>>& word_frequencies, const char& hash);
     static string create_link(const unordered_map<string, unordered_map<string, int>>& word_frequencies, unsigned long  hash);
     static string create_image(const string& image);
     static unsigned int hash_url(const string& input);