diff --git a/data_structures/queue/CMakeLists.txt b/data_structures/queue/CMakeLists.txt
index 969936730..434d3bb45 100644
--- a/data_structures/queue/CMakeLists.txt
+++ b/data_structures/queue/CMakeLists.txt
@@ -1,5 +1,7 @@
+add_library(libqueue OBJECT queue.h queue.cpp)
 add_executable( test_queue 
-    queue.cpp 
     test_queue.cpp 
 )
+target_link_libraries(test_queue PUBLIC libqueue)
+
 install(TARGETS test_queue DESTINATION "bin/data_structures")
diff --git a/data_structures/queue/queue.cpp b/data_structures/queue/queue.cpp
index a7055bb14..9d5f9b9df 100644
--- a/data_structures/queue/queue.cpp
+++ b/data_structures/queue/queue.cpp
@@ -1,8 +1,7 @@
-#include "queue.h"
-#include <assert.h>
-#include <iostream>
+#include "./queue.h"
 
-using namespace std;
+#include <cassert>
+#include <iostream>
 
 /* Default constructor*/
 template <class Kind>
@@ -20,13 +19,13 @@ queue<Kind>::~queue() {}
 template <class Kind>
 void queue<Kind>::display() {
     node<Kind> *current = queueFront;
-    cout << "Front --> ";
+    std::cout << "Front --> ";
     while (current != NULL) {
-        cout << current->data << "    ";
+        std::cout << current->data << "    ";
         current = current->next;
     }
-    cout << endl;
-    cout << "Size of queue: " << size << endl;
+    std::cout << std::endl;
+    std::cout << "Size of queue: " << size << std::endl;
 }
 
 /* Determine whether the queue is empty */
@@ -75,6 +74,10 @@ void queue<Kind>::deQueue() {
         delete temp;
         size--;
     } else {
-        cout << "Queue is empty !" << endl;
+        std::cout << "Queue is empty !" << std::endl;
     }
 }
+
+#include <string>
+/** force instantiate to export the type class */
+template class queue<std::string>;
diff --git a/data_structures/queue/queue.h b/data_structures/queue/queue.h
index d1305fc81..d55ee3864 100644
--- a/data_structures/queue/queue.h
+++ b/data_structures/queue/queue.h
@@ -1,31 +1,31 @@
 /* This class specifies the basic operation on a queue as a linked list */
-#ifndef QUEUE_H
-#define QUEUE_H
+#ifndef DATA_STRUCTURES_QUEUE_QUEUE_H_
+#define DATA_STRUCTURES_QUEUE_QUEUE_H_
 
-/* Definition of the node */
+/** Definition of the node */
 template <class Kind>
 struct node {
     Kind data;
     node<Kind> *next;
 };
 
-/* Definition of the queue class */
+/** Definition of the queue class */
 template <class Kind>
 class queue {
  public:
-    void display();          /* Show queue */
-    queue();                 /* Default constructor*/
-    ~queue();                /* Destructor */
-    bool isEmptyQueue();     /* Determine whether the queue is empty */
-    void enQueue(Kind item); /* Add new item to the queue */
-    Kind front();            /* Return the first element of the queue */
-    void deQueue();          /* Remove the top element of the queue */
+    void display();          /**< Show queue */
+    queue();                 /**< Default constructor*/
+    ~queue();                /**< Destructor */
+    bool isEmptyQueue();     /**< Determine whether the queue is empty */
+    void enQueue(Kind item); /**< Add new item to the queue */
+    Kind front();            /**< Return the first element of the queue */
+    void deQueue();          /**< Remove the top element of the queue */
     void clear();
 
  private:
-    node<Kind> *queueFront; /* Pointer to the front of the queue */
-    node<Kind> *queueRear;  /* Pointer to the rear of the queue  */
+    node<Kind> *queueFront; /**< Pointer to the front of the queue */
+    node<Kind> *queueRear;  /**< Pointer to the rear of the queue  */
     int size;
 };
 
-#endif
+#endif  // DATA_STRUCTURES_QUEUE_QUEUE_H_
diff --git a/data_structures/queue/test_queue.cpp b/data_structures/queue/test_queue.cpp
index 7f0923f78..387ccf2f7 100644
--- a/data_structures/queue/test_queue.cpp
+++ b/data_structures/queue/test_queue.cpp
@@ -1,41 +1,41 @@
 #include <iostream>
 #include <string>
-#include "queue.cpp"
-#include "queue.h"
 
-using namespace std;
+#include "./queue.h"
 
 int main() {
-    queue<string> q;
-    cout << "---------------------- Test construct ----------------------"
-         << endl;
+    queue<std::string> q;
+    std::cout << "---------------------- Test construct ----------------------"
+              << std::endl;
     q.display();
-    cout << "---------------------- Test isEmptyQueue ----------------------"
-         << endl;
+    std::cout
+        << "---------------------- Test isEmptyQueue ----------------------"
+        << std::endl;
     if (q.isEmptyQueue())
-        cout << "PASS" << endl;
+        std::cout << "PASS" << std::endl;
     else
-        cout << "FAIL" << endl;
-    cout << "---------------------- Test enQueue ----------------------"
-         << endl;
-    cout << "After Hai, Jeff, Tom, Jkingston go into queue: " << endl;
+        std::cout << "FAIL" << std::endl;
+    std::cout << "---------------------- Test enQueue ----------------------"
+              << std::endl;
+    std::cout << "After Hai, Jeff, Tom, Jkingston go into queue: " << std::endl;
     q.enQueue("Hai");
     q.enQueue("Jeff");
     q.enQueue("Tom");
     q.enQueue("Jkingston");
     q.display();
-    cout << "---------------------- Test front ----------------------" << endl;
-    string value = q.front();
+    std::cout << "---------------------- Test front ----------------------"
+              << std::endl;
+    std::string value = q.front();
     if (value == "Hai")
-        cout << "PASS" << endl;
+        std::cout << "PASS" << std::endl;
     else
-        cout << "FAIL" << endl;
-    cout << "---------------------- Test deQueue ----------------------"
-         << endl;
+        std::cout << "FAIL" << std::endl;
+    std::cout << "---------------------- Test deQueue ----------------------"
+              << std::endl;
     q.display();
     q.deQueue();
     q.deQueue();
-    cout << "After Hai, Jeff left the queue: " << endl;
+    std::cout << "After Hai, Jeff left the queue: " << std::endl;
     q.display();
     return 0;
 }
diff --git a/data_structures/stk/main.cpp b/data_structures/stk/main.cpp
index 11215ac4b..a6048c4c9 100644
--- a/data_structures/stk/main.cpp
+++ b/data_structures/stk/main.cpp
@@ -14,7 +14,7 @@
 #include <iostream>
 #include <string>
 
-#include "stack.h"
+#include "./stack.h"
 
 int main(int argc, char* argv[]) {
     double GPA;