From 1b191968ba95e2bf42054498024a284309e7bf85 Mon Sep 17 00:00:00 2001
From: ishwar <ishwargowda100@gmail.com>
Date: Sun, 14 Nov 2021 13:34:54 +0530
Subject: [PATCH 1/9] adding c++ implementation of stack and queue

---
 contents/stacks_and_queues/code/c++/queue.cpp | 102 ++++++++++++++++++
 contents/stacks_and_queues/code/c++/stack.cpp |  83 ++++++++++++++
 .../stacks_and_queues/stacks_and_queues.md    |   4 +
 3 files changed, 189 insertions(+)
 create mode 100644 contents/stacks_and_queues/code/c++/queue.cpp
 create mode 100644 contents/stacks_and_queues/code/c++/stack.cpp

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/c++/queue.cpp
new file mode 100644
index 000000000..f94140e26
--- /dev/null
+++ b/contents/stacks_and_queues/code/c++/queue.cpp
@@ -0,0 +1,102 @@
+#include<iostream>
+using namespace std;
+
+
+namespace my {
+    /**
+     *implementation using parameterised linked list
+     * [value][next] -> [value][next] -> ... -> [value][next] -> [value][next]
+     *  (front Node)   (intermediat elements)    (rear Node)      (dummy Node)
+     */
+    template<typename T>
+    struct Node {
+        /**
+        * next: will store next Node(right) address
+        */
+        T value;
+        Node<T>* next;
+        Node(const T& V) : value(V), next(nullptr) { }
+    };
+
+    template<typename T>
+    class queue {
+    private:
+        /**
+         * variabel: _front points to left most node , right most  Node is dummy Node
+         * count: will keep track of current number of elements present in stack excluding dummy Node
+         */
+        Node<T>* _front;
+        Node<T>* rear;
+        size_t count;
+    public:
+        queue() : _front(nullptr), rear(nullptr), count(0ULL) {
+            _front = rear = new Node<T>(0); // creating a dummy Node
+        }
+
+        void push(const T& element) {
+            Node<T>* new_node = new Node<T>(element);  // create New Node
+            if (count > 0) {
+                new_node->next = rear->next; // make buffer point to dummy Node
+                rear->next = new_node;       // make rear Node point to buffer
+                rear = new_node;             // make rear pointer to point to buffer
+            } else {
+                new_node->next = rear;
+                rear = _front = new_node;
+            }
+            count = count + 1;
+        }
+
+        void dequeue() {
+            if (count > 0) {
+                Node<T>* buffer = _front;
+                _front = _front->next;
+                count = count - 1;
+                delete buffer;
+            }
+            rear = (count != 0) ? rear : _front;
+        }
+
+        T& front() const { return _front->value; }
+        // returning reference can very usefull if someone wants to modify _front element
+
+        size_t size() const { return count; }
+
+        bool empty() const { return count == 0; }
+
+        ~queue() {
+            for (Node<T>* pointer = _front; pointer != nullptr;) {
+                Node<T>* buffer = pointer;
+                pointer = pointer->next;
+                delete buffer;
+            }
+        }
+    };
+}
+
+int main() {
+    my::queue<int> Q;
+
+    Q.push(0);
+    Q.push(1);
+    Q.push(2);
+    Q.push(3);
+
+    cout << "count: " << Q.size() << endl;
+
+    Q.front() = 10;
+
+    while (Q.empty() != true) {
+        cout << "element: " << Q.front() << endl;
+        Q.dequeue();
+    }
+
+    Q.push(3);
+    Q.push(6);
+    cout << "count: " << Q.size() << endl;
+    while (Q.empty() != true) {
+        cout << "element: " << Q.front() << endl;
+        Q.dequeue();
+    }
+    return 0;
+}
+
diff --git a/contents/stacks_and_queues/code/c++/stack.cpp b/contents/stacks_and_queues/code/c++/stack.cpp
new file mode 100644
index 000000000..5324cb521
--- /dev/null
+++ b/contents/stacks_and_queues/code/c++/stack.cpp
@@ -0,0 +1,83 @@
+
+#include<iostream>
+using namespace std;
+
+namespace my {
+    /**
+     *implementation using parameterised linked list
+     * [value][next] -> [value][next] -> ... -> [value][next]
+     * (top Node)      (intermediat Nodes)      (dummy Node)
+     * left most Node represents_top element of stack
+     * right most Node is a dummy Node
+     */
+    template<typename T>
+    struct Node {
+        /**
+        * next: will store next Node(right) address
+        */
+        T value;
+        Node<T>* next;
+        Node(const T& V) : value(V), next(nullptr) { }
+    };
+
+    template<typename T>
+    class stack {
+    private:
+        /**
+         * variabel:_top points to left most node , right most  Node is dummy Node
+         * count: will keep track of current number of elements present in stack excluding dummy Node
+         */
+        Node<T>* _top;
+        size_t count;
+    public:
+        stack() : _top(nullptr), count(0ULL) {
+            _top = new Node<T>(0); // creating a dummy node
+        }
+
+        void push(const T& element) {
+            Node<T>* buffer = new Node<T>(element);
+            buffer->next = _top;
+            _top = buffer;
+            count = count + 1;
+        }
+
+        void pop() {
+            if (count > 0) {
+                Node<T>* buffer = _top;
+                _top = _top->next;
+                count = count - 1;
+                delete buffer;
+            }
+        }
+
+        T& top() const { return _top->value; }
+        // returning reference can very usefull if someone wants to modify top element
+
+        size_t size() const { return count; }
+
+        bool empty() const { return count == 0; }
+
+        ~stack() {
+            for (Node<T>* pointer = _top; pointer != nullptr;) {
+                Node<T>* buffer = pointer;
+                pointer = pointer->next;
+                delete buffer;
+            }
+        }
+    };
+}
+
+int main() {
+    my::stack<int> S;
+    S.push(0);
+    S.push(1);
+    S.push(2);
+    S.push(3);
+    cout << "size: " << S.size() << endl;
+    S.top() = 10;
+    while (S.empty() != true) {
+        cout << "element: " << S.top() << endl;
+        S.pop();
+    }
+    return 0;
+}
diff --git a/contents/stacks_and_queues/stacks_and_queues.md b/contents/stacks_and_queues/stacks_and_queues.md
index 89a77be9a..4d9908e55 100644
--- a/contents/stacks_and_queues/stacks_and_queues.md
+++ b/contents/stacks_and_queues/stacks_and_queues.md
@@ -20,6 +20,8 @@ Here is a simple implementation of a stack:
 [import, lang:"typescript"](code/typescript/stack.ts)
 {% sample lang="java" %}
 [import, lang:"java"](code/java/Stack.java)
+{% sample lang = "cpp"%}
+[import, lang:"cpp"](code/c++/stack.cpp)
 {% endmethod %}
 
 Here is a simple implementation of a queue:
@@ -28,6 +30,8 @@ Here is a simple implementation of a queue:
 [import, lang:"typescript"](code/typescript/queue.ts)
 {% sample lang="java" %}
 [import, lang:"java" ](code/java/Queue.java)
+{% sample lang = "cpp"%}
+[import, lang:"cpp"](code/c++/queue.cpp)
 {% endmethod %}
 
 

From feb723c8e0459ecc487bae657abbc6f8f97b7fd9 Mon Sep 17 00:00:00 2001
From: ishwar <ishwargowda100@gmail.com>
Date: Sun, 14 Nov 2021 13:52:57 +0530
Subject: [PATCH 2/9] improved some comments

---
 contents/stacks_and_queues/code/c++/queue.cpp | 20 +++++++++----------
 contents/stacks_and_queues/code/c++/stack.cpp |  9 +++------
 2 files changed, 12 insertions(+), 17 deletions(-)

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/c++/queue.cpp
index f94140e26..f2a406850 100644
--- a/contents/stacks_and_queues/code/c++/queue.cpp
+++ b/contents/stacks_and_queues/code/c++/queue.cpp
@@ -1,17 +1,16 @@
 #include<iostream>
 using namespace std;
 
-
 namespace my {
     /**
-     *implementation using parameterised linked list
+     * parameterised type implementation using linked list
      * [value][next] -> [value][next] -> ... -> [value][next] -> [value][next]
-     *  (front Node)   (intermediat elements)    (rear Node)      (dummy Node)
+     *  (front Node)   (intermediat Nodes)    (rear Node)      (dummy Node)
      */
     template<typename T>
     struct Node {
         /**
-        * next: will store next Node(right) address
+        * next: will store right Node address
         */
         T value;
         Node<T>* next;
@@ -22,8 +21,9 @@ namespace my {
     class queue {
     private:
         /**
-         * variabel: _front points to left most node , right most  Node is dummy Node
-         * count: will keep track of current number of elements present in stack excluding dummy Node
+         * _front :  points to left most node
+         * count: keeps track of current number of elements present in queue excluding dummy Node
+         * rear:  points to most recent Node added into the queue, which is just left size of dummy Node
          */
         Node<T>* _front;
         Node<T>* rear;
@@ -36,9 +36,9 @@ namespace my {
         void push(const T& element) {
             Node<T>* new_node = new Node<T>(element);  // create New Node
             if (count > 0) {
-                new_node->next = rear->next; // make buffer point to dummy Node
-                rear->next = new_node;       // make rear Node point to buffer
-                rear = new_node;             // make rear pointer to point to buffer
+                new_node->next = rear->next; // make new Node point to dummy Node
+                rear->next = new_node;       // make rear Node point to new Node
+                rear = new_node;             // make rear Node's pointer to point to new Node
             } else {
                 new_node->next = rear;
                 rear = _front = new_node;
@@ -80,9 +80,7 @@ int main() {
     Q.push(1);
     Q.push(2);
     Q.push(3);
-
     cout << "count: " << Q.size() << endl;
-
     Q.front() = 10;
 
     while (Q.empty() != true) {
diff --git a/contents/stacks_and_queues/code/c++/stack.cpp b/contents/stacks_and_queues/code/c++/stack.cpp
index 5324cb521..0d8b61e0a 100644
--- a/contents/stacks_and_queues/code/c++/stack.cpp
+++ b/contents/stacks_and_queues/code/c++/stack.cpp
@@ -1,4 +1,3 @@
-
 #include<iostream>
 using namespace std;
 
@@ -7,13 +6,11 @@ namespace my {
      *implementation using parameterised linked list
      * [value][next] -> [value][next] -> ... -> [value][next]
      * (top Node)      (intermediat Nodes)      (dummy Node)
-     * left most Node represents_top element of stack
-     * right most Node is a dummy Node
      */
     template<typename T>
     struct Node {
         /**
-        * next: will store next Node(right) address
+        * next: will store right Node address
         */
         T value;
         Node<T>* next;
@@ -24,8 +21,8 @@ namespace my {
     class stack {
     private:
         /**
-         * variabel:_top points to left most node , right most  Node is dummy Node
-         * count: will keep track of current number of elements present in stack excluding dummy Node
+         * _top:  points to left most node
+         * count: keeps track of current number of elements present in stack excluding dummy Node
          */
         Node<T>* _top;
         size_t count;

From 2a89d6082a5a425840f4f77ae65eb56e478e1b65 Mon Sep 17 00:00:00 2001
From: Ishwar <60176567+ishwar00@users.noreply.github.com>
Date: Sun, 14 Nov 2021 15:21:42 +0530
Subject: [PATCH 3/9] Update contents/stacks_and_queues/code/c++/queue.cpp

adding version T const& front() const

Co-authored-by: Dimitri Belopopsky <ShadowMitia@users.noreply.github.com>
---
 contents/stacks_and_queues/code/c++/queue.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/c++/queue.cpp
index f2a406850..49d30515f 100644
--- a/contents/stacks_and_queues/code/c++/queue.cpp
+++ b/contents/stacks_and_queues/code/c++/queue.cpp
@@ -57,6 +57,7 @@ namespace my {
         }
 
         T& front() const { return _front->value; }
+        T const& front() const { return _front->value; }
         // returning reference can very usefull if someone wants to modify _front element
 
         size_t size() const { return count; }

From 1bfc0c431c1605b3546204dc56df857ec65114a2 Mon Sep 17 00:00:00 2001
From: Ishwar <60176567+ishwar00@users.noreply.github.com>
Date: Sun, 14 Nov 2021 15:23:34 +0530
Subject: [PATCH 4/9] Update contents/stacks_and_queues/code/c++/queue.cpp

removing unnecessary comment

Co-authored-by: Dimitri Belopopsky <ShadowMitia@users.noreply.github.com>
---
 contents/stacks_and_queues/code/c++/queue.cpp | 1 -
 1 file changed, 1 deletion(-)

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/c++/queue.cpp
index 49d30515f..55e74f049 100644
--- a/contents/stacks_and_queues/code/c++/queue.cpp
+++ b/contents/stacks_and_queues/code/c++/queue.cpp
@@ -58,7 +58,6 @@ namespace my {
 
         T& front() const { return _front->value; }
         T const& front() const { return _front->value; }
-        // returning reference can very usefull if someone wants to modify _front element
 
         size_t size() const { return count; }
 

From 9d9a24542870451e9d58309a9040e70c7c84272c Mon Sep 17 00:00:00 2001
From: ishwar <ishwargowda100@gmail.com>
Date: Sun, 14 Nov 2021 23:35:30 +0530
Subject: [PATCH 5/9] improved implementation

---
 contents/stacks_and_queues/code/c++/queue.cpp | 82 +++++++++----------
 contents/stacks_and_queues/code/c++/stack.cpp | 58 ++++++-------
 2 files changed, 67 insertions(+), 73 deletions(-)

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/c++/queue.cpp
index 55e74f049..5dbcd639e 100644
--- a/contents/stacks_and_queues/code/c++/queue.cpp
+++ b/contents/stacks_and_queues/code/c++/queue.cpp
@@ -1,11 +1,13 @@
 #include<iostream>
-using namespace std;
+#include<memory>
+#include<cassert>
 
 namespace my {
+    const char endl = '\n';
     /**
-     * parameterised type implementation using linked list
-     * [value][next] -> [value][next] -> ... -> [value][next] -> [value][next]
-     *  (front Node)   (intermediat Nodes)    (rear Node)      (dummy Node)
+     * implementation using linked list
+     * [value][next] -> [value][next] -> ... -> [value][next]
+     *  (front Node)   (intermediat Nodes)     (rear Node)
      */
     template<typename T>
     struct Node {
@@ -13,61 +15,63 @@ namespace my {
         * next: will store right Node address
         */
         T value;
-        Node<T>* next;
-        Node(const T& V) : value(V), next(nullptr) { }
+        std::shared_ptr<Node<T>> next;
+        Node(const T& V) : value(V) { }
     };
 
     template<typename T>
     class queue {
     private:
         /**
-         * _front :  points to left most node
-         * count: keeps track of current number of elements present in queue excluding dummy Node
-         * rear:  points to most recent Node added into the queue, which is just left size of dummy Node
+         * front_pointer:  points to left most node
+         * count: keeps track of current number of elements present in queue
+         * rear_pointer:  points to most recent Node added into the queue, which is right most Node
          */
-        Node<T>* _front;
-        Node<T>* rear;
+        std::shared_ptr<Node<T>> front_pointer;
+        std::shared_ptr<Node<T>> rear_pointer;
         size_t count;
     public:
-        queue() : _front(nullptr), rear(nullptr), count(0ULL) {
-            _front = rear = new Node<T>(0); // creating a dummy Node
-        }
+        queue() : count(0ULL) { }
 
         void push(const T& element) {
-            Node<T>* new_node = new Node<T>(element);  // create New Node
+            auto new_node = std::make_shared<Node<T>>(element);
             if (count > 0) {
-                new_node->next = rear->next; // make new Node point to dummy Node
-                rear->next = new_node;       // make rear Node point to new Node
-                rear = new_node;             // make rear Node's pointer to point to new Node
+                new_node->next = front_pointer;
+                front_pointer = new_node;
             } else {
-                new_node->next = rear;
-                rear = _front = new_node;
+                rear_pointer = front_pointer = new_node;
             }
             count = count + 1;
         }
 
         void dequeue() {
-            if (count > 0) {
-                Node<T>* buffer = _front;
-                _front = _front->next;
+            if (count > 1) {
+                front_pointer = front_pointer->next;
+                count = count - 1;
+            } else if (count == 1) {
+                front_pointer.reset();
+                rear_pointer.reset();
                 count = count - 1;
-                delete buffer;
             }
-            rear = (count != 0) ? rear : _front;
         }
 
-        T& front() const { return _front->value; }
-        T const& front() const { return _front->value; }
+        T& front() {
+            assert(count > 0 && "calling front on an empty queue");
+            return front_pointer->value;
+        }
+
+        T const& front() const {
+            assert(count > 0 && "calling front on an empty queue");
+            return front_pointer->value;
+        }
 
         size_t size() const { return count; }
 
         bool empty() const { return count == 0; }
 
         ~queue() {
-            for (Node<T>* pointer = _front; pointer != nullptr;) {
-                Node<T>* buffer = pointer;
-                pointer = pointer->next;
-                delete buffer;
+            while (front_pointer.get() != nullptr) {
+                front_pointer = front_pointer->next;
             }
         }
     };
@@ -75,26 +79,14 @@ namespace my {
 
 int main() {
     my::queue<int> Q;
-
     Q.push(0);
-    Q.push(1);
-    Q.push(2);
     Q.push(3);
-    cout << "count: " << Q.size() << endl;
+    std::cout << "count: " << Q.size() << my::endl;
     Q.front() = 10;
 
     while (Q.empty() != true) {
-        cout << "element: " << Q.front() << endl;
-        Q.dequeue();
-    }
-
-    Q.push(3);
-    Q.push(6);
-    cout << "count: " << Q.size() << endl;
-    while (Q.empty() != true) {
-        cout << "element: " << Q.front() << endl;
+        std::cout << "element: " << Q.front() << my::endl;
         Q.dequeue();
     }
     return 0;
 }
-
diff --git a/contents/stacks_and_queues/code/c++/stack.cpp b/contents/stacks_and_queues/code/c++/stack.cpp
index 0d8b61e0a..3c91824e3 100644
--- a/contents/stacks_and_queues/code/c++/stack.cpp
+++ b/contents/stacks_and_queues/code/c++/stack.cpp
@@ -1,11 +1,14 @@
 #include<iostream>
-using namespace std;
+#include<cassert>
+#include<memory>
 
 namespace my {
+    const char endl = '\n';
     /**
-     *implementation using parameterised linked list
+     * implementation using linked list
      * [value][next] -> [value][next] -> ... -> [value][next]
-     * (top Node)      (intermediat Nodes)      (dummy Node)
+     * (top Node)      (intermediat Nodes)
+     * left most Node represents top element of stack
      */
     template<typename T>
     struct Node {
@@ -13,52 +16,54 @@ namespace my {
         * next: will store right Node address
         */
         T value;
-        Node<T>* next;
-        Node(const T& V) : value(V), next(nullptr) { }
+        std::unique_ptr<Node<T>> next;
+        Node(const T& V) : value(V) { }
     };
 
     template<typename T>
     class stack {
     private:
         /**
-         * _top:  points to left most node
-         * count: keeps track of current number of elements present in stack excluding dummy Node
+         * top_pointer: points to left most node
+         * count: keeps track of current number of elements present in stack
          */
-        Node<T>* _top;
+        std::unique_ptr<Node<T>> top_pointer;
         size_t count;
     public:
-        stack() : _top(nullptr), count(0ULL) {
-            _top = new Node<T>(0); // creating a dummy node
-        }
+        stack() : count(0ULL) { }
 
         void push(const T& element) {
-            Node<T>* buffer = new Node<T>(element);
-            buffer->next = _top;
-            _top = buffer;
+            auto new_node = std::make_unique<Node<T>>(element);
+            new_node->next = std::move(top_pointer);
+            top_pointer = std::move(new_node);
             count = count + 1;
         }
 
         void pop() {
             if (count > 0) {
-                Node<T>* buffer = _top;
-                _top = _top->next;
+                top_pointer = std::move(top_pointer->next);
                 count = count - 1;
-                delete buffer;
             }
         }
 
-        T& top() const { return _top->value; }
-        // returning reference can very usefull if someone wants to modify top element
+        T& top() {
+            assert(count > 0 and "calling top() on an empty stack");
+            return top_pointer->value;
+        }
+        // returning mutable reference can very be usefull if someone wants to modify top element
+
+        T const& top() const {
+            assert(count > 0 and "calling top() on an empty stack");
+            return top_pointer->value;
+        }
 
         size_t size() const { return count; }
 
         bool empty() const { return count == 0; }
 
         ~stack() {
-            for (Node<T>* pointer = _top; pointer != nullptr;) {
-                Node<T>* buffer = pointer;
-                pointer = pointer->next;
-                delete buffer;
+            while (top_pointer.get() != nullptr) {
+                top_pointer = std::move(top_pointer->next);
             }
         }
     };
@@ -66,14 +71,11 @@ namespace my {
 
 int main() {
     my::stack<int> S;
-    S.push(0);
-    S.push(1);
-    S.push(2);
     S.push(3);
-    cout << "size: " << S.size() << endl;
+    std::cout << "size: " << S.size() << my::endl;
     S.top() = 10;
     while (S.empty() != true) {
-        cout << "element: " << S.top() << endl;
+        std::cout << "element: " << S.top() << my::endl;
         S.pop();
     }
     return 0;

From 7af16dda7359f696b8e86f9066fa788ee2c3c3cc Mon Sep 17 00:00:00 2001
From: ishwar <ishwargowda100@gmail.com>
Date: Mon, 15 Nov 2021 00:18:51 +0530
Subject: [PATCH 6/9] fixed queue implementation

---
 contents/stacks_and_queues/code/c++/queue.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/c++/queue.cpp
index 5dbcd639e..377f361c5 100644
--- a/contents/stacks_and_queues/code/c++/queue.cpp
+++ b/contents/stacks_and_queues/code/c++/queue.cpp
@@ -36,8 +36,8 @@ namespace my {
         void push(const T& element) {
             auto new_node = std::make_shared<Node<T>>(element);
             if (count > 0) {
-                new_node->next = front_pointer;
-                front_pointer = new_node;
+                rear_pointer->next = new_node;
+                rear_pointer = new_node;
             } else {
                 rear_pointer = front_pointer = new_node;
             }
@@ -79,10 +79,12 @@ namespace my {
 
 int main() {
     my::queue<int> Q;
-    Q.push(0);
+    Q.push(-1);
+    Q.push(1);
+    Q.push(2);
     Q.push(3);
     std::cout << "count: " << Q.size() << my::endl;
-    Q.front() = 10;
+    Q.front() = 0;
 
     while (Q.empty() != true) {
         std::cout << "element: " << Q.front() << my::endl;

From 7221c9b2b75788ff0d970e0dc41afb5ddd2279b1 Mon Sep 17 00:00:00 2001
From: ishwar <ishwargowda100@gmail.com>
Date: Wed, 17 Nov 2021 01:17:07 +0530
Subject: [PATCH 7/9] renamed queue API push as enqueue

---
 contents/stacks_and_queues/code/c++/queue.cpp | 24 +++++++++----------
 contents/stacks_and_queues/code/c++/stack.cpp | 21 +++++++++-------
 2 files changed, 23 insertions(+), 22 deletions(-)

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/c++/queue.cpp
index 377f361c5..3917668df 100644
--- a/contents/stacks_and_queues/code/c++/queue.cpp
+++ b/contents/stacks_and_queues/code/c++/queue.cpp
@@ -33,7 +33,7 @@ namespace my {
     public:
         queue() : count(0ULL) { }
 
-        void push(const T& element) {
+        void enqueue(const T& element) {
             auto new_node = std::make_shared<Node<T>>(element);
             if (count > 0) {
                 rear_pointer->next = new_node;
@@ -78,17 +78,15 @@ namespace my {
 }
 
 int main() {
-    my::queue<int> Q;
-    Q.push(-1);
-    Q.push(1);
-    Q.push(2);
-    Q.push(3);
-    std::cout << "count: " << Q.size() << my::endl;
-    Q.front() = 0;
+  my::queue<int> intQueue;
+  intQueue.enqueue(4);
+  intQueue.enqueue(5);
+  intQueue.enqueue(9);
 
-    while (Q.empty() != true) {
-        std::cout << "element: " << Q.front() << my::endl;
-        Q.dequeue();
-    }
-    return 0;
+  int frontElement = intQueue.front();
+  intQueue.dequeue();
+  std::cout << frontElement << my::endl;
+  std::cout << intQueue.size() << my::endl;
+  std::cout << intQueue.front() << my::endl;
+  return 0;
 }
diff --git a/contents/stacks_and_queues/code/c++/stack.cpp b/contents/stacks_and_queues/code/c++/stack.cpp
index 3c91824e3..5a7c1151c 100644
--- a/contents/stacks_and_queues/code/c++/stack.cpp
+++ b/contents/stacks_and_queues/code/c++/stack.cpp
@@ -70,13 +70,16 @@ namespace my {
 }
 
 int main() {
-    my::stack<int> S;
-    S.push(3);
-    std::cout << "size: " << S.size() << my::endl;
-    S.top() = 10;
-    while (S.empty() != true) {
-        std::cout << "element: " << S.top() << my::endl;
-        S.pop();
-    }
-    return 0;
+  my::stack<int> intStack;
+
+  intStack.push(4);
+  intStack.push(5);
+  intStack.push(9);
+
+  int topElement = intStack.top();
+  intStack.pop();
+  std::cout << topElement << my::endl;
+  std::cout << intStack.size() << my::endl;
+  std::cout << intStack.top() << my::endl;
+  return 0;
 }

From b878ed0372049352c69ed54e6fc8b7806e6cb71a Mon Sep 17 00:00:00 2001
From: Dimitri Belopopsky <dimitri@belopopsky.com>
Date: Wed, 12 Jan 2022 09:42:22 +0100
Subject: [PATCH 8/9] Rename code folder to cpp

---
 contents/stacks_and_queues/code/{c++ => cpp}/queue.cpp | 0
 contents/stacks_and_queues/code/{c++ => cpp}/stack.cpp | 0
 contents/stacks_and_queues/stacks_and_queues.md        | 4 ++--
 3 files changed, 2 insertions(+), 2 deletions(-)
 rename contents/stacks_and_queues/code/{c++ => cpp}/queue.cpp (100%)
 rename contents/stacks_and_queues/code/{c++ => cpp}/stack.cpp (100%)

diff --git a/contents/stacks_and_queues/code/c++/queue.cpp b/contents/stacks_and_queues/code/cpp/queue.cpp
similarity index 100%
rename from contents/stacks_and_queues/code/c++/queue.cpp
rename to contents/stacks_and_queues/code/cpp/queue.cpp
diff --git a/contents/stacks_and_queues/code/c++/stack.cpp b/contents/stacks_and_queues/code/cpp/stack.cpp
similarity index 100%
rename from contents/stacks_and_queues/code/c++/stack.cpp
rename to contents/stacks_and_queues/code/cpp/stack.cpp
diff --git a/contents/stacks_and_queues/stacks_and_queues.md b/contents/stacks_and_queues/stacks_and_queues.md
index 57ae65654..e72857b96 100644
--- a/contents/stacks_and_queues/stacks_and_queues.md
+++ b/contents/stacks_and_queues/stacks_and_queues.md
@@ -21,7 +21,7 @@ Here is a simple implementation of a stack:
 {% sample lang="java" %}
 [import, lang:"java"](code/java/Stack.java)
 {% sample lang = "cpp"%}
-[import, lang:"cpp"](code/c++/stack.cpp)
+[import, lang:"cpp"](code/cpp/stack.cpp)
 [import, lang:"java"](code/java/StackTest.java)
 {% sample lang="rust" %}
 [import, lang:"rust"](code/rust/Stack.rs)
@@ -34,7 +34,7 @@ Here is a simple implementation of a queue:
 {% sample lang="java" %}
 [import, lang:"java" ](code/java/Queue.java)
 {% sample lang = "cpp"%}
-[import, lang:"cpp"](code/c++/queue.cpp)
+[import, lang:"cpp"](code/cpp/queue.cpp)
 [import, lang:"java" ](code/java/QueueTest.java)
 {% sample lang="rust" %}
 [import, lang:"rust" ](code/rust/Queue.rs)

From 00ee930a5617310988d9c682e3e723fd03ca1c90 Mon Sep 17 00:00:00 2001
From: Dimitri Belopopsky <dimitri@belopopsky.com>
Date: Wed, 12 Jan 2022 09:46:43 +0100
Subject: [PATCH 9/9] Inline newlines

---
 contents/stacks_and_queues/code/cpp/queue.cpp | 7 +++----
 contents/stacks_and_queues/code/cpp/stack.cpp | 7 +++----
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/contents/stacks_and_queues/code/cpp/queue.cpp b/contents/stacks_and_queues/code/cpp/queue.cpp
index 3917668df..009abbd06 100644
--- a/contents/stacks_and_queues/code/cpp/queue.cpp
+++ b/contents/stacks_and_queues/code/cpp/queue.cpp
@@ -3,7 +3,6 @@
 #include<cassert>
 
 namespace my {
-    const char endl = '\n';
     /**
      * implementation using linked list
      * [value][next] -> [value][next] -> ... -> [value][next]
@@ -85,8 +84,8 @@ int main() {
 
   int frontElement = intQueue.front();
   intQueue.dequeue();
-  std::cout << frontElement << my::endl;
-  std::cout << intQueue.size() << my::endl;
-  std::cout << intQueue.front() << my::endl;
+  std::cout << frontElement << '\n';
+  std::cout << intQueue.size() << '\n';
+  std::cout << intQueue.front() << '\n';
   return 0;
 }
diff --git a/contents/stacks_and_queues/code/cpp/stack.cpp b/contents/stacks_and_queues/code/cpp/stack.cpp
index 5a7c1151c..0d13beda3 100644
--- a/contents/stacks_and_queues/code/cpp/stack.cpp
+++ b/contents/stacks_and_queues/code/cpp/stack.cpp
@@ -3,7 +3,6 @@
 #include<memory>
 
 namespace my {
-    const char endl = '\n';
     /**
      * implementation using linked list
      * [value][next] -> [value][next] -> ... -> [value][next]
@@ -78,8 +77,8 @@ int main() {
 
   int topElement = intStack.top();
   intStack.pop();
-  std::cout << topElement << my::endl;
-  std::cout << intStack.size() << my::endl;
-  std::cout << intStack.top() << my::endl;
+  std::cout << topElement << '\n';
+  std::cout << intStack.size() << '\n';
+  std::cout << intStack.top() << '\n';
   return 0;
 }