From 939e98d5b206aacef037aa9073c76ca10ea71f46 Mon Sep 17 00:00:00 2001
From: David Hackbarth <david@lyrebird-studio.com>
Date: Sat, 21 Feb 2026 10:38:58 +0100
Subject: [PATCH] Add `containers` module with initial implementation and
 integrate into CMake build system.

---
 .idea/.name                   |  1 +
 .idea/editor.xml              | 96 +++++++++++++++++++++++++++++++++++
 .idea/hwr2024_b.iml           |  8 +--
 .idea/misc.xml                |  9 ++++
 cpp/.idea/.name               |  2 +-
 cpp/.idea/misc.xml            |  2 +-
 cpp/CMakeLists.txt            |  1 +
 cpp/classes/CMakeLists.txt    |  4 +-
 cpp/classes/ClassA.cpp        | 30 +++++++++++
 cpp/classes/ClassA.h          |  9 +++-
 cpp/classes/IComparable.h     |  5 ++
 cpp/classes/main.cpp          | 20 ++++++++
 cpp/containers/CMakeLists.txt |  8 +++
 cpp/containers/functions.cpp  | 14 +++++
 cpp/containers/functions.h    | 10 ++++
 cpp/containers/main.cpp       | 65 ++++++++++++++++++++++++
 16 files changed, 272 insertions(+), 12 deletions(-)
 create mode 100644 .idea/.name
 create mode 100644 .idea/misc.xml
 create mode 100644 cpp/containers/CMakeLists.txt
 create mode 100644 cpp/containers/functions.cpp
 create mode 100644 cpp/containers/functions.h
 create mode 100644 cpp/containers/main.cpp

diff --git a/.idea/.name b/.idea/.name
new file mode 100644
index 0000000..70a1f63
--- /dev/null
+++ b/.idea/.name
@@ -0,0 +1 @@
+containers
\ No newline at end of file
diff --git a/.idea/editor.xml b/.idea/editor.xml
index fef3201..8d0e15e 100644
--- a/.idea/editor.xml
+++ b/.idea/editor.xml
@@ -245,5 +245,101 @@
     <option name="/Default/CodeInspection/Highlighting/InspectionSeverities/=IfStdIsConstantEvaluatedCanBeReplaced/@EntryIndexedValue" value="SUGGESTION" type="string" />
     <option name="/Default/CodeInspection/Highlighting/InspectionSeverities/=StdIsConstantEvaluatedWillAlwaysEvaluateToConstant/@EntryIndexedValue" value="WARNING" type="string" />
     <option name="/Default/CodeInspection/Highlighting/InspectionSeverities/=StringLiteralTypo/@EntryIndexedValue" value="DO_NOT_SHOW" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppClangFormat/EnableClangFormatSupport/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_ARGUMENT/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_BINARY_EXPRESSIONS_CHAIN/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_CALLS_CHAIN/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_EXPRESSION/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_EXTENDS_LIST/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_FOR_STMT/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_PARAMETER/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_TYPE_ARGUMENT/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTILINE_TYPE_PARAMETER/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_MULTIPLE_DECLARATION/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ALIGN_TERNARY/@EntryValue" value="ALIGN_ALL" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/ANONYMOUS_METHOD_DECLARATION_BRACES/@EntryValue" value="END_OF_LINE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/BLANK_LINES_AROUND_CLASS_DEFINITION/@EntryValue" value="1" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/BLANK_LINES_AROUND_DECLARATIONS/@EntryValue" value="0" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/BLANK_LINES_AROUND_FUNCTION_DECLARATION/@EntryValue" value="1" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/BLANK_LINES_AROUND_FUNCTION_DEFINITION/@EntryValue" value="1" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/BREAK_TEMPLATE_DECLARATION/@EntryValue" value="LINE_BREAK" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/CASE_BLOCK_BRACES/@EntryValue" value="END_OF_LINE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/CONTINUOUS_LINE_INDENT/@EntryValue" value="Double" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INDENT_ACCESS_SPECIFIERS_FROM_CLASS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INDENT_CASE_FROM_SWITCH/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INDENT_CLASS_MEMBERS_FROM_ACCESS_SPECIFIERS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INDENT_COMMENT/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INDENT_SIZE/@EntryValue" value="4" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INDENT_STYLE/@EntryValue" value="Space" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INITIALIZER_BRACES/@EntryValue" value="END_OF_LINE_NO_SPACE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INT_ALIGN_EQ/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/INVOCABLE_DECLARATION_BRACES/@EntryValue" value="END_OF_LINE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/KEEP_BLANK_LINES_IN_CODE/@EntryValue" value="2" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/KEEP_BLANK_LINES_IN_DECLARATIONS/@EntryValue" value="2" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/KEEP_USER_LINEBREAKS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/LINE_BREAK_AFTER_COLON_IN_MEMBER_INITIALIZER_LISTS/@EntryValue" value="ON_SINGLE_LINE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/MEMBER_INITIALIZER_LIST_STYLE/@EntryValue" value="DO_NOT_CHANGE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/NAMESPACE_DECLARATION_BRACES/@EntryValue" value="END_OF_LINE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/NAMESPACE_INDENTATION/@EntryValue" value="All" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/OTHER_BRACES/@EntryValue" value="END_OF_LINE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/PLACE_CATCH_ON_NEW_LINE/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/PLACE_ELSE_ON_NEW_LINE/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/PLACE_NAMESPACE_DEFINITIONS_ON_SAME_LINE/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/PLACE_WHILE_ON_NEW_LINE/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SIMPLE_BLOCK_STYLE/@EntryValue" value="DO_NOT_CHANGE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_CAST_EXPRESSION_PARENTHESES/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_COLON_IN_BITFIELD_DECLARATOR/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_COMMA_IN_TEMPLATE_ARGS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_COMMA_IN_TEMPLATE_PARAMS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_EXTENDS_COLON/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_FOR_COLON/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_FOR_SEMICOLON/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_PTR_IN_DATA_MEMBER/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_PTR_IN_DATA_MEMBERS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_PTR_IN_METHOD/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_PTR_IN_NESTED_DECLARATOR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_REF_IN_DATA_MEMBER/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_REF_IN_DATA_MEMBERS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_REF_IN_METHOD/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_AFTER_UNARY_OPERATOR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_COLON_IN_BITFIELD_DECLARATOR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_EXTENDS_COLON/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_FOR_COLON/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_FOR_SEMICOLON/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_PTR_IN_ABSTRACT_DECL/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_PTR_IN_DATA_MEMBER/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_PTR_IN_DATA_MEMBERS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_PTR_IN_METHOD/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_REF_IN_ABSTRACT_DECL/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_REF_IN_DATA_MEMBER/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_REF_IN_DATA_MEMBERS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_REF_IN_METHOD/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_TEMPLATE_ARGS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BEFORE_TEMPLATE_PARAMS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_BETWEEN_CLOSING_ANGLE_BRACKETS_IN_TEMPLATE_ARGS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_ARRAY_ACCESS_BRACKETS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_CAST_EXPRESSION_PARENTHESES/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_DECLARATION_PARENTHESES/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_EMPTY_BLOCKS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_EMPTY_INITIALIZER_BRACES/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_EMPTY_METHOD_PARENTHESES/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_EMPTY_TEMPLATE_PARAMS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_INITIALIZER_BRACES/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_TEMPLATE_ARGS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPACE_WITHIN_TEMPLATE_PARAMS/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/SPECIAL_ELSE_IF_TREATMENT/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/TAB_WIDTH/@EntryValue" value="4" type="int" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/TYPE_DECLARATION_BRACES/@EntryValue" value="END_OF_LINE" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_AFTER_BINARY_OPSIGN/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_AFTER_DECLARATION_LPAR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_AFTER_INVOCATION_LPAR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_ARGUMENTS_STYLE/@EntryValue" value="WRAP_IF_LONG" type="string" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_BEFORE_DECLARATION_LPAR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_BEFORE_DECLARATION_RPAR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_BEFORE_INVOCATION_LPAR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_BEFORE_INVOCATION_RPAR/@EntryValue" value="false" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_BEFORE_TERNARY_OPSIGNS/@EntryValue" value="true" type="bool" />
+    <option name="/Default/CodeStyle/CodeFormatting/CppFormatting/WRAP_PARAMETERS_STYLE/@EntryValue" value="WRAP_IF_LONG" type="string" />
+    <option name="/Default/CodeStyle/EditorConfig/EnableClangFormatSupport/@EntryValue" value="false" type="bool" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/hwr2024_b.iml b/.idea/hwr2024_b.iml
index bc2cd87..4c94235 100644
--- a/.idea/hwr2024_b.iml
+++ b/.idea/hwr2024_b.iml
@@ -1,8 +1,2 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<module type="CPP_MODULE" version="4">
-  <component name="NewModuleRootManager">
-    <content url="file://$MODULE_DIR$" />
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>
\ No newline at end of file
+<module classpath="CIDR" type="CPP_MODULE" version="4" />
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000..f1cca2e
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CMakePythonSetting">
+    <option name="pythonIntegrationState" value="YES" />
+  </component>
+  <component name="CMakeWorkspace" PROJECT_DIR="$PROJECT_DIR$/cpp/containers">
+    <contentRoot DIR="$PROJECT_DIR$" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/cpp/.idea/.name b/cpp/.idea/.name
index 5ba3f42..70a1f63 100644
--- a/cpp/.idea/.name
+++ b/cpp/.idea/.name
@@ -1 +1 @@
-pointer
\ No newline at end of file
+containers
\ No newline at end of file
diff --git a/cpp/.idea/misc.xml b/cpp/.idea/misc.xml
index 7a865bb..cb02c5a 100644
--- a/cpp/.idea/misc.xml
+++ b/cpp/.idea/misc.xml
@@ -3,7 +3,7 @@
   <component name="CMakePythonSetting">
     <option name="pythonIntegrationState" value="YES" />
   </component>
-  <component name="CMakeWorkspace" PROJECT_DIR="$PROJECT_DIR$/classes">
+  <component name="CMakeWorkspace" PROJECT_DIR="$PROJECT_DIR$/containers">
     <contentRoot DIR="$PROJECT_DIR$" />
   </component>
 </project>
\ No newline at end of file
diff --git a/cpp/CMakeLists.txt b/cpp/CMakeLists.txt
index 6400fcd..25484a0 100644
--- a/cpp/CMakeLists.txt
+++ b/cpp/CMakeLists.txt
@@ -4,3 +4,4 @@ project(cpp)
 add_subdirectory(intro)
 add_subdirectory(pointer)
 add_subdirectory(classes)
+add_subdirectory(containers)
diff --git a/cpp/classes/CMakeLists.txt b/cpp/classes/CMakeLists.txt
index 4c41146..ebe070b 100644
--- a/cpp/classes/CMakeLists.txt
+++ b/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)
diff --git a/cpp/classes/ClassA.cpp b/cpp/classes/ClassA.cpp
index 135d247..d51d878 100644
--- a/cpp/classes/ClassA.cpp
+++ b/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;
 }
diff --git a/cpp/classes/ClassA.h b/cpp/classes/ClassA.h
index 8d1434a..2e3fe2f 100644
--- a/cpp/classes/ClassA.h
+++ b/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
\ No newline at end of file
diff --git a/cpp/classes/IComparable.h b/cpp/classes/IComparable.h
index 08b9186..3307ed3 100644
--- a/cpp/classes/IComparable.h
+++ b/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;
 };
 
diff --git a/cpp/classes/main.cpp b/cpp/classes/main.cpp
index 29461c1..2be1926 100644
--- a/cpp/classes/main.cpp
+++ b/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;
 }
diff --git a/cpp/containers/CMakeLists.txt b/cpp/containers/CMakeLists.txt
new file mode 100644
index 0000000..20cfbd9
--- /dev/null
+++ b/cpp/containers/CMakeLists.txt
@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 4.1)
+project(containers)
+
+set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_FLAGS -pedantic-errors)
+
+add_executable(containers main.cpp
+        functions.cpp)
diff --git a/cpp/containers/functions.cpp b/cpp/containers/functions.cpp
new file mode 100644
index 0000000..daf66ec
--- /dev/null
+++ b/cpp/containers/functions.cpp
@@ -0,0 +1,14 @@
+#include <iostream>
+
+void printArrayAtPosition(int *array, int index) {
+    if (array == nullptr) {
+        return;
+    }
+    if (index < 0) {
+        return;
+    }
+
+    std::cout << "size of array: " << sizeof(array) << std::endl;
+    std::cout << array[index] << std::endl;
+}
+
diff --git a/cpp/containers/functions.h b/cpp/containers/functions.h
new file mode 100644
index 0000000..fdedda8
--- /dev/null
+++ b/cpp/containers/functions.h
@@ -0,0 +1,10 @@
+//
+// Created by David Hackbarth on 20.02.26.
+//
+
+#ifndef CONTAINERS_FUNCTIONS_H
+#define CONTAINERS_FUNCTIONS_H
+
+void printArrayAtPosition(int* array, int index);
+
+#endif //CONTAINERS_FUNCTIONS_H
diff --git a/cpp/containers/main.cpp b/cpp/containers/main.cpp
new file mode 100644
index 0000000..f90e098
--- /dev/null
+++ b/cpp/containers/main.cpp
@@ -0,0 +1,65 @@
+#include <iostream>
+#include <vector>
+#include <list>
+
+#include "functions.h"
+
+typedef std::list<float> FloatList;
+typedef FloatList::iterator FloatListIterator;
+
+int main() {
+    // C array
+    int numbers[5] = {1, 2, 3, 4, 5}; // stack array
+    const int count = 10;
+    // count *= 2;
+    int numbers2[count];
+    numbers2[0] = 10;
+
+    int* numbers3 = new int[count]; // heap array
+    delete[] numbers3;
+    numbers3 = nullptr;
+
+    // numbers[10] = 100;
+
+    std::cout << "size of numbers: " << sizeof(numbers) << std::endl;
+
+    printArrayAtPosition(numbers, 19);
+
+    // vector
+    std::vector<int> v;
+    v.push_back(10);
+    v.push_back(20);
+    v.push_back(30);
+    v.pop_back();
+    v[1] = 100;
+
+    std::cout << "v: " << v.size() << "/" << v.capacity() << std::endl;
+
+    v.push_back(40);
+
+    std::cout << "v: " << v.size() << "/" << v.capacity() << std::endl;
+
+    v.push_back(50);
+
+    std::cout << "v: " << v.size() << "/" << v.capacity() << std::endl;
+
+    v.push_back(60);
+
+    std::cout << "v: " << v.size() << "/" << v.capacity() << std::endl;
+
+    v.reserve(100);
+
+    std::cout << "v: " << v.size() << "/" << v.capacity() << std::endl;
+
+    printArrayAtPosition(v.data(), 1);
+
+    // list
+    std::list<int> l;
+    std::list<int>::iterator it;
+
+    for (it = l.begin(); it != l.end(); ++it) {
+        std::cout << *it << std::endl;
+    }
+
+    return 0;
+}
\ No newline at end of file