Add containers module with initial implementation and integrate into CMake build system.

cpp/classes/CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 4.1)
-project(pointer)
+project(classes)
 
 set(CMAKE_CXX_STANDARD 20)
 
-add_executable(pointer main.cpp ClassA.cpp)
+add_executable(classes main.cpp ClassA.cpp)

cpp/classes/ClassA.cpp

@@ -2,6 +2,36 @@
 
 #include <iostream>
 
+ClassA::ClassA() : IComparable(), _number(0), _pDecimal(new float(0.0f)) {
+    std::cout << "ClassA()" << std::endl;
+
+    // _pDecimal = new float(0.0f);
+}
+
+ClassA::ClassA(const ClassA &other) :
+    IComparable(),
+    _number(other._number),
+    _pDecimal(new float(*other._pDecimal)) {
+
+    std::cout << "ClassA(const ClassA &other)" << std::endl;
+
+    // // for presentation only
+    // // shallow copy
+    // _number = other._number;
+    // *_pDecimal = *other._pDecimal;
+    //
+    // // deep copy
+    // _number = other._number;
+    // _pDecimal = new float(*other._pDecimal);
+}
+
+ClassA::~ClassA() {
+    std::cout << "~ClassA()" << std::endl;
+
+    delete _pDecimal;
+    _pDecimal = nullptr;
+}
+
 void ClassA::Print() {
     std::cout << "ClassA" << std::endl;
 }

cpp/classes/ClassA.h

@@ -8,16 +8,23 @@ class ClassA : public IComparable {
 
 public:
     // public
+    ClassA(); // default constructor
+    ClassA(const ClassA& other); // copy constructor
+    ~ClassA() override; // destructor
+
     void Print();
     int CompareTo(IComparable* other) override;
 
+    const float& GetDecimal() const { return *_pDecimal; }
+    void SetDecimal(float decimal) { *_pDecimal = decimal; }
+
 protected:
     // protected
 
 private:
     // private
     int _number = 0;
+    float* _pDecimal = nullptr;
 };
 
-
 #endif //POINTER_CLASSA_H

cpp/classes/IComparable.h

@@ -1,8 +1,13 @@
 #ifndef POINTER_ICOMPARABLE_H
 #define POINTER_ICOMPARABLE_H
+#include <iostream>
 
 class IComparable {
 public:
+    // only for presentation purposes
+    IComparable() { std::cout << "IComparable()" << std::endl; }
+    virtual ~IComparable() { std::cout << "~IComparable()" << std::endl; }
+
     virtual int CompareTo(IComparable* other) = 0;
 };
 

cpp/classes/main.cpp

@@ -1,4 +1,5 @@
 #include "ClassA.h"
+#include <list>
 
 int main() {
     ClassA a{};
@@ -20,5 +21,24 @@ int main() {
     delete pComparable;
     pComparable = nullptr;
 
+    // copy object
+    ClassA a2 = a;
+
+    std::list<ClassA> list;
+    std::list<ClassA>::iterator it;
+
+    for (it = list.begin(); it != list.end(); ++it) {
+       it->Print();
+    }
+
+    std::list<IComparable*> list2;
+    std::list<IComparable*>::iterator it2;
+
+    for (it2 = list2.begin(); it2 != list2.end(); ++it2) {
+        (*it2)->CompareTo(&a);
+    }
+
+    IComparable* pComparables[10];
+
     return 0;
 }