Add containers project with CMake setup and array-related functionality

- Implement `printArrayAtPosition` in `functions.cpp` with input validation.
- Created `main.cpp` to demonstrate array operations using C arrays and `std::vector`.
- Updated `ClassA` and `IComparable` with constructors, destructors, and deep copy logic.
- Adjusted IntelliJ project configuration for new containers module.

cpp/classes/ClassA.cpp

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