extracted method with adding issue

.gitignore

@@ -1,2 +0,0 @@
-# Project exclude paths
-/out/

.idea/misc.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_X" default="true" project-jdk-name="openjdk-20" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_18" default="true" project-jdk-name="openjdk-18" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>

OOP_IO-2x_2023.iml

@@ -1,11 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module type="JAVA_MODULE" version="4">
-  <component name="NewModuleRootManager" inherit-compiler-output="true">
-    <exclude-output />
-    <content url="file://$MODULE_DIR$">
-      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
-    </content>
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>

lab1_with_extracted_method/Program.cs

@@ -0,0 +1,61 @@
+using System;
+
+public class Lab1
+{
+    public static void Main(String[] args)
+    {
+        /*o1 = +
+         c3 = 0
+         o2 = *
+         c7 = short */
+
+        // var A = 4;
+        // short B = 3;
+        // var N = 10;
+        // var M = 10;
+        //
+        // var C = 1;
+        // var s = 0;
+        //
+        // bool divisionByZero=false;
+
+
+        Calculation(4, 3, 10, 10, 1, false);
+    }
+
+    public static void Calculation(int A, int C, int N, short B, int M, bool divisionByZero)
+    {
+        var s = 0;
+        if ((A <= -C && -C <= N) || (B <= 0 && 0 <= M))
+        {
+            Console.WriteLine("Division by zero!");
+            return;
+        }
+
+        for (int i = A; i <= N; i++)
+        {
+            if (i + C == 0)
+            {
+                Console.WriteLine("Division by zero!");
+                divisionByZero = true;
+                break;
+            }
+
+            for (short j = B; j <= M; j++)
+            {
+                if (j == 0)
+                {
+                    Console.WriteLine("Оскільки j = 0, то сума просто буде 0");
+                    break;
+                }
+
+                s += (i * j) / (i + C);
+            }
+        }
+
+        if (!divisionByZero)
+        {
+            Console.WriteLine($"s = {s};");
+        }
+    }
+}

lab2.iml

@@ -1,11 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module type="JAVA_MODULE" version="4">
-  <component name="NewModuleRootManager" inherit-compiler-output="true">
-    <exclude-output />
-    <content url="file://$MODULE_DIR$">
-      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
-    </content>
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>

laboratorna1/Program.cs

@@ -0,0 +1,52 @@
+using System;
+
+public class Lab1
+{
+    public static void Main(String[] args)
+    {
+        /*o1 = +
+         c3 = 0
+         o2 = *
+         c7 = short */
+
+         var A = 4;
+         short B = 3;
+         var N = 10;
+         var M = 10;
+
+         var C = 1;
+         var s = 0;
+
+         bool divisionByZero=false;
+
+
+        if ((A <= -C && -C <= N) || (B <= 0 && 0 <= M))
+        {
+            Console.WriteLine("Division by zero!");
+            return;
+        }
+      
+        for (int i = A; i <= N; i++)
+        {
+            if (i + C == 0) { 
+                Console.WriteLine("Division by zero!");
+                divisionByZero = true;
+                break; 
+            }
+            for (short j = B; j <= M; j++)
+            {
+                if (j == 0) {
+                    Console.WriteLine("Оскільки j = 0, то сума просто буде 0");
+                    break;
+                }
+                s += (i * j) / (i + C);
+            }
+        }
+
+        if (!divisionByZero)
+        {
+            Console.WriteLine($"s = {s};" );
+        }
+
+    }
+}

src/Lab1.java

@@ -0,0 +1,58 @@
+public class Lab1 {
+    public static void main(String[] args) {
+//        char c = 'a' + '1';
+        char c = 97;
+//        char c = '1';
+        System.out.println(c);
+        System.out.println((int) c);
+        c++;
+        System.out.println(c);
+        System.out.println((int) c);
+        System.out.println((double)'1'/'3');
+
+//        System.out.println( (double) 0 / 0 );
+//        System.out.println( Math.sqrt(-1) );
+        double s = 0;
+        /*for (int i = 1; i <= 3; i++) { // 1) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> i = 1, 2) <20><><EFBFBD><EFBFBD> <20> <= 3, 3) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 䳿 <20> <20><> <20><><EFBFBD><EFBFBD><EFBFBD>,
+            System.out.println(i);     // 4) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20> <20><> 1, 5) <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> <20><> <20><><EFBFBD><EFBFBD><EFBFBD> 2
+//            s = s + i;
+            s += i;
+        }*/
+        /*int[] array = new int[2];
+        for (int i = 0; i < array.length; i++) {
+
+        }*/
+        final int A = -3;
+        final int B = 0;
+        final int N = 2;
+        final int M = 2;
+
+        final int C = 1;
+//        boolean wasDivisionByZero = false;
+//        todo char
+//        todo[clear code] think about avoiding brackets
+        if ((A <= -C && -C <= N) || (B <= 0 && 0 <= M)) {
+            System.out.println("Division by zero!");
+            return;
+        }
+/*myLabel:*/for (int i = A; i <= N /*&& !wasDivisionByZero*/; i++) {
+            /*if (i + C == 0) { // todo optimize
+                System.out.println("Division by zero!");
+                wasDivisionByZero = true;
+                break; //todo flag vs return;
+            }*/
+            for (int j = B; j <= M; j++) {
+                /*if (j == 0) {
+                    System.out.println("Division by zero!");
+                    return;
+//                    wasDivisionByZero = true;
+//                    break myLabel;
+                }*/
+                s += (double) (i / j) / (i + C);
+            }
+        }
+//        if (!wasDivisionByZero) {
+            System.out.println("s = " + s);
+//        }
+    }
+}

src/Lab2.java

@@ -0,0 +1,26 @@
+public class Lab2 {
+    public static void main(String[] args) {
+        int[] array = {1, 2, 3};
+        /*for (int i = 0; i < array.length; i++) {
+            if (i % 2 == 0) {
+                System.out.println("!" + array[i]);
+            } else {
+                System.out.println("?" + array[i]);
+            }
+        }*/
+
+        for (int i = 0; i < array.length; i+=2) {
+            System.out.println("!" + array[i]);
+        }
+
+        for (int i = 1; i < array.length; i+=2) {
+            System.out.println("?" + array[i]);
+        }
+
+//        зубчасті матриці
+        int[][] matrix = {
+                {1, 2},
+                {3}
+        };
+    }
+}

src/Lab5.java

@@ -1,231 +0,0 @@
-import java.util.ArrayList;
-import java.util.List;
-
-class Letter {
-    private char character;
-
-    public Letter(char character) {
-        this.character = character;
-    }
-
-    public char getCharacter() {
-        return character;
-    }
-
-    @Override
-    public String toString() {
-        return String.valueOf(character);
-    }
-}
-
-class Word {
-    private List<Letter> letters;
-
-    public Word(List<Letter> letters) {
-        this.letters = letters;
-    }
-
-    public List<Letter> getLetters() {
-        return letters;
-    }
-
-    @Override
-    public String toString() {
-        StringBuilder wordBuilder = new StringBuilder();
-        for (Letter letter : letters) {
-            wordBuilder.append(letter.getCharacter());
-        }
-        return wordBuilder.toString();
-    }
-}
-
-class Sentence {
-    private List<Object> components;
-
-    public Sentence(List<Object> components) {
-        this.components = components;
-    }
-
-    public List<Object> getComponents() {
-        return components;
-    }
-
-    @Override
-    public String toString() {
-        StringBuilder sentenceBuilder = new StringBuilder();
-        for (Object component : components) {
-            if (component instanceof Word) {
-                List<Letter> letters = ((Word) component).getLetters();
-                for (Letter letter : letters) {
-                    sentenceBuilder.append(letter.getCharacter());
-                }
-            } else if (component instanceof PunctuationMark) {
-                sentenceBuilder.append(((PunctuationMark) component).getMark());
-            }
-            sentenceBuilder.append(" ");
-        }
-        return sentenceBuilder.toString().trim();
-    }
-}
-
-class PunctuationMark {
-    private char mark;
-
-    public PunctuationMark(char mark) {
-        this.mark = mark;
-    }
-
-    public char getMark() {
-        return mark;
-    }
-
-    @Override
-    public String toString() {
-        return String.valueOf(mark);
-    }
-}
-
-class Text {
-    private List<Sentence> sentences;
-
-    public Text(List<Sentence> sentences) {
-        this.sentences = sentences;
-    }
-
-    public List<Sentence> getSentences() {
-        return sentences;
-    }
-
-    @Override
-    public String toString() {
-        StringBuilder textBuilder = new StringBuilder();
-        for (Sentence sentence : sentences) {
-            textBuilder.append(sentence.toString()).append(". ");
-        }
-        return textBuilder.toString().trim();
-    }
-}
-
-public class Lab5 {
-    public static void main(String[] args) {
-        System.out.println("C17 = " + 2425%17);
-        StringBuffer sentence = new StringBuffer("об'єктно-орієнтована мова програмування , випущена 1995 року компанією" +
-                " Сан Майкросістемс , як основний компонент платформи Джава." +
-                " З 2009 року мовою займається компанія Оракл , яка того року придбала Сан Майкросістемс. В офіційній" +
-                " реалізації Джава-програми компілюються у байт-код , який при виконанні інтерпретується віртуальною" +
-                " машиною для конкретної платформи");
-
-        // Заміна послідовності табуляцій та пробілів одним пробілом
-        String cleanedText = replaceTabsAndSpaces(sentence.toString());
-
-        // Розбиття тексту на речення
-        String[] sentenceArray = cleanedText.split("\\.");
-
-        List<Sentence> sentences = new ArrayList<>();
-        List<Character> punctuationMarks = new ArrayList<>();
-
-        for (String s : sentenceArray) {
-            // Розбиття речення на слова та розділові знаки
-            String[] components = s.trim().split("\\s+");
-
-            List<Object> sentenceComponents = new ArrayList<>();
-
-            for (String component : components) {
-                if (isPunctuationMark(component)) {
-                    // Додавання розділових знаків
-                    char mark = component.charAt(component.length() - 1);
-                    punctuationMarks.add(mark);
-                    sentenceComponents.add(new PunctuationMark(mark));
-                } else {
-                    // Створення слова
-                    List<Letter> letters = new ArrayList<>();
-                    for (char c : component.toCharArray()) {
-                        letters.add(new Letter(c));
-                    }
-                    sentenceComponents.add(new Word(letters));
-                }
-            }
-
-            sentences.add(new Sentence(sentenceComponents));
-        }
-
-        // Створення тексту
-        Text text = new Text(sentences);
-
-        // Виведення букв, слів та речень
-        List<Sentence> allSentences = text.getSentences();
-        for (Sentence s : allSentences) {
-            List<Object> components = s.getComponents();
-
-            for (Object component : components) {
-                if (component instanceof Word) {
-                    System.out.println("Слово: " + component);
-                    List<Letter> letters = ((Word) component).getLetters();
-                    for (Letter letter : letters) {
-                        System.out.println("Літера: " + letter.getCharacter());
-                    }
-                } else if (component instanceof PunctuationMark) {
-                    System.out.println("Розділовий знак: " + ((PunctuationMark) component).getMark());
-                }
-            }
-
-            System.out.println("Речення: " + s.toString());
-            System.out.println();
-        }
-
-        // Виведення розділових знаків
-        System.out.println("Розділові знаки:");
-        for (Character mark : punctuationMarks) {
-            System.out.println(mark);
-        }
-
-        // Виведення масиву речень з пробілами
-        System.out.println("Масив речень:");
-        for (Sentence s : allSentences) {
-            System.out.println(s.toString());
-        }
-
-        // Видалення слів заданої довжини, починаючи з приголосної літери
-        removeWords(allSentences);
-
-        // Виведення оновленого тексту
-        System.out.println("Оновлений текст:");
-        System.out.println(text.toString());
-
-    }
-
-
-    // Функція для заміни табуляцій та пробілів одним пробілом
-    private static String replaceTabsAndSpaces(String text) {
-        return text.replaceAll("\\s+", " ");
-    }
-
-    // Функція для перевірки, чи є рядок розділовим знаком
-    private static boolean isPunctuationMark(String text) {
-        return text.matches(".*[,.]$");
-    }
-
-    // Функція для видалення слів заданої довжини, починаючи з приголосної літери
-    private static void removeWords(List<Sentence> sentences) {
-        String consonants = "бвгґджзклмнпрстфхцчшщ";
-        for (Sentence sentence : sentences) {
-            List<Object> components = sentence.getComponents();
-            List<Object> componentsToRemove = new ArrayList<>();
-
-            for (Object component : components) {
-                if (component instanceof Word) {
-                    Word word = (Word) component;
-                    List<Letter> letters = word.getLetters();
-                    int wordLength = letters.size();
-                    char firstLetter = letters.get(0).getCharacter();
-
-                    if ((wordLength > 5) && (wordLength < 9) && consonants.contains(String.valueOf(firstLetter))) {
-                        componentsToRemove.add(component);
-                    }
-                }
-            }
-
-            components.removeAll(componentsToRemove);
-        }
-    }
-}

src/Lab6.java

@@ -1,117 +0,0 @@
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Comparator;
-import java.util.List;
-import java.util.Scanner;
-
-class Train {
-    private List<PassengerCarriage> carriages;
-
-    public Train(List<PassengerCarriage> carriages) {
-        this.carriages = carriages;
-    }
-
-    public int getTotalPassengerCount() {
-        int totalPassengerCount = 0;
-        for (PassengerCarriage carriage : carriages) {
-            totalPassengerCount += carriage.getPassengerCount();
-        }
-        return totalPassengerCount;
-    }
-
-    public int getTotalLuggageCount() {
-        int totalLuggageCount = 0;
-        for (PassengerCarriage carriage : carriages) {
-            totalLuggageCount += carriage.getLuggageCount();
-        }
-        return totalLuggageCount;
-    }
-
-    public void sortCarriagesByComfortLevel() {
-        Collections.sort(carriages, new Comparator<PassengerCarriage>() {
-            @Override
-            public int compare(PassengerCarriage c1, PassengerCarriage c2) {
-                return c1.getComfortLevel() - c2.getComfortLevel();
-            }
-        });
-    }
-
-    public PassengerCarriage findCarriageByPassengerCount(int minPassengers, int maxPassengers) {
-        for (PassengerCarriage carriage : carriages) {
-            int passengerCount = carriage.getPassengerCount();
-            if (passengerCount >= minPassengers && passengerCount <= maxPassengers) {
-                return carriage;
-            }
-        }
-        return null;
-    }
-}
-
-class PassengerCarriage {
-    private int passengerCount;
-    private int luggageCount;
-    private int comfortLevel;
-
-    public PassengerCarriage(int passengerCount, int luggageCount, int comfortLevel) {
-        this.passengerCount = passengerCount;
-        this.luggageCount = luggageCount;
-        this.comfortLevel = comfortLevel;
-    }
-
-    public int getPassengerCount() {
-        return passengerCount;
-    }
-
-    public int getLuggageCount() {
-        return luggageCount;
-    }
-
-    public int getComfortLevel() {
-        return comfortLevel;
-    }
-}
-
-public class Lab6 {
-    public static void main(String[] args) {
-        // Задаємо характеристики вагонів
-        List<PassengerCarriage> carriages = new ArrayList<>();
-        carriages.add(new PassengerCarriage(30, 64, 3));
-        carriages.add(new PassengerCarriage(53, 126, 2));
-        carriages.add(new PassengerCarriage(89, 164, 1));
-
-        Train train = new Train(carriages);
-
-        int totalPassengerCount = train.getTotalPassengerCount();
-        int totalLuggageCount = train.getTotalLuggageCount();
-
-        System.out.println("Кількість всіх пасажирів: " + totalPassengerCount);
-        System.out.println("Кількість всього багажу: " + totalLuggageCount);
-
-        train.sortCarriagesByComfortLevel();
-
-        System.out.println("Вагони відсортовані за рівнем комфорту:");
-        for (PassengerCarriage carriage : carriages) {
-            System.out.println("Кількість пасажирів: " + carriage.getPassengerCount() +
-                    ", Рівень комфорту: " + carriage.getComfortLevel());
-        }
-
-        Scanner scanner = new Scanner(System.in);
-
-        System.out.print("Введіть мінімальну кількість пасажирів: ");
-        int minPassengers = scanner.nextInt();
-        System.out.print("Введіть максимальну кількість пасажирів: ");
-        int maxPassengers = scanner.nextInt();
-
-        PassengerCarriage carriage = train.findCarriageByPassengerCount(minPassengers, maxPassengers);
-
-        if (carriage != null) {
-            System.out.println("Вагон знайдений за кількість пасажирів між " +
-                    minPassengers + " та " + maxPassengers);
-            System.out.println("Кількість пасажирів: " + carriage.getPassengerCount() +
-                    ", Рівень комфорту: " + carriage.getComfortLevel());
-        } else {
-            System.out.println("Вагон не знайдений за кількістю пасажирів " +
-                    minPassengers + " між " + maxPassengers);
-        }
-    }
-}

src/Main.java

@@ -0,0 +1,42 @@
+public class Main {
+    public static void main(String[] args) {
+        System.out.println(args[2]);
+        System.out.println("Hello world!");
+//        System.out.println(1);
+
+        int a = 1;
+        int b = 2;
+        int c = 1;
+        int d = 1;
+
+        System.out.println(2&1);
+        System.out.println(2|1);
+        int aa = 2;
+
+        /*if (aa) {
+
+        }*/
+
+//        System.out.println("a"&"b");
+        System.out.println('a'&'b');
+
+        if ((a > b) & MyBooleanMethod()) {
+            System.out.println("?????????????????????????");
+        }
+
+
+    }
+
+    static boolean MyBooleanMethod() {
+        System.out.println("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
+        return true;
+    }
+
+    void myFunction() {
+
+    }
+
+    int myFunction2() {
+        return 1;
+    }
+}

src/encapsulationInheritancePolymorphism/Encapsulation.java

@@ -0,0 +1,20 @@
+package encapsulationInheritancePolymorphism;
+
+public class Encapsulation {
+    /*private*/ int field;
+    private int field2;
+//    int a = 1;
+
+    public void myMethodForTheField () {
+        System.out.println(field);
+    }
+
+    public void myMethodForTheField2 () {
+        System.out.println(field);
+    }
+
+    public void myMethodForTheFieldAndTheField2 () {
+        System.out.println(field);
+    }
+}
+

src/encapsulationInheritancePolymorphism/EncapsulationInheritancePolymorphism.java

@@ -0,0 +1,10 @@
+package encapsulationInheritancePolymorphism;
+
+public class EncapsulationInheritancePolymorphism {
+
+    public static void main(String[] args) {
+        int a = 1;
+//        var b = 2;
+//        System.out.println(b);
+    }
+}

src/encapsulationInheritancePolymorphism/Main.java

@@ -0,0 +1,14 @@
+package encapsulationInheritancePolymorphism;
+
+public class Main {
+    public static void main(String[] args) {
+        Student student = new Student();
+
+
+
+
+        //...
+
+        student.setFaculty("FPM", "MO-22");
+    }
+}

src/encapsulationInheritancePolymorphism/Student.java

@@ -0,0 +1,18 @@
+package encapsulationInheritancePolymorphism;
+
+public class Student {
+    private String name;
+    private String surname;
+    private String group;
+    private String faculty;
+
+
+    public String getName() {
+        return name;
+    }
+
+    public void setFaculty(String faculty, String group) {
+        this.faculty = faculty;
+        this.group = group;
+    }
+}

src/encapsulationInheritancePolymorphism/inheritance/ElectricEngine.java

@@ -0,0 +1,9 @@
+package encapsulationInheritancePolymorphism.inheritance;
+
+public class ElectricEngine extends Engine {
+    private String batteryType;
+
+    /*private class Engine {
+        private int power;
+    }*/
+}

src/encapsulationInheritancePolymorphism/inheritance/Engine.java

@@ -0,0 +1,5 @@
+package encapsulationInheritancePolymorphism.inheritance;
+
+public class Engine {
+    private int power;
+}

src/encapsulationInheritancePolymorphism/inheritance/FuelEngine.java

@@ -0,0 +1,5 @@
+package encapsulationInheritancePolymorphism.inheritance;
+
+public class FuelEngine extends Engine {
+    private String fuelType;
+}

src/encapsulationInheritancePolymorphism/inheritance/Main.java

@@ -0,0 +1,8 @@
+package encapsulationInheritancePolymorphism.inheritance;
+
+public class Main {
+    public static void main(String[] args) {
+        ElectricEngine electricEngine = new ElectricEngine(); // створення нового об'єкту (екземпляру) класу ElectricEngine
+        FuelEngine fuelEngine = new FuelEngine();
+    }
+}

src/encapsulationInheritancePolymorphism/polymorphism/ElectricEngine.java

@@ -0,0 +1,14 @@
+package encapsulationInheritancePolymorphism.polymorphism;
+
+public class ElectricEngine extends Engine {
+    private String batteryType;
+
+    @Override
+    public int getPower() {
+        return 20;
+    }
+
+    /*private class Engine {
+        private int power;
+    }*/
+}

src/encapsulationInheritancePolymorphism/polymorphism/Engine.java

@@ -0,0 +1,9 @@
+package encapsulationInheritancePolymorphism.polymorphism;
+
+public class Engine {
+    private int power;
+
+    public int getPower() {
+        return power;
+    }
+}

src/encapsulationInheritancePolymorphism/polymorphism/FuelEngine.java

@@ -0,0 +1,10 @@
+package encapsulationInheritancePolymorphism.polymorphism;
+
+public class FuelEngine extends Engine {
+    private String fuelType;
+
+    @Override
+    public int getPower() {
+        return 50;
+    }
+}

src/encapsulationInheritancePolymorphism/polymorphism/Main.java

@@ -0,0 +1,38 @@
+package encapsulationInheritancePolymorphism.polymorphism;
+
+/*import encapsulationInheritancePolymorphism.inheritance.ElectricEngine;
+import encapsulationInheritancePolymorphism.inheritance.FuelEngine;*/
+
+public class Main {
+    public static void main(String[] args) {
+        /*encapsulationInheritancePolymorphism.inheritance.*/ElectricEngine electricEngine = new ElectricEngine(); // створення нового об'єкту (екземпляру) класу ElectricEngine
+        /*encapsulationInheritancePolymorphism.inheritance.*/FuelEngine fuelEngine = new FuelEngine();
+
+        Engine engine1 = fuelEngine;
+
+        Engine[] engines = {
+                electricEngine,
+                fuelEngine
+        };
+
+        for (Engine engine : engines) {
+            System.out.println(engine.getPower());
+        }
+
+        /*for (int i = 0; i < engines.length; i++) {
+            System.out.println(engines[i].getPower());
+        }*/
+
+//        +
+        int a = 1;
+        int b = 1;
+        int c = a + b;
+        System.out.println(c);
+
+
+        String sA = "1";
+        String sB = "1";
+        String sC = sA + sB;
+        System.out.println(sC);
+    }
+}

src/encapsulationInheritancePolymorphism/polymorphism/enhanced/ElectricEngine.java

@@ -0,0 +1,19 @@
+package encapsulationInheritancePolymorphism.polymorphism.enhanced;
+
+public class ElectricEngine extends Engine {
+    private String batteryType;
+    private int chargeLevel = 9;
+    private int criticalChargeLevel = 10;
+    private float coefficientCriticalPowerCut = 0.1f;
+
+    @Override
+    public int getPower() {
+        return chargeLevel > criticalChargeLevel
+                ? super.getPower()
+                : (int) (super.getPower() * coefficientCriticalPowerCut);
+    }
+
+    /*private class Engine {
+        private int power;
+    }*/
+}

src/encapsulationInheritancePolymorphism/polymorphism/enhanced/Engine.java

@@ -0,0 +1,9 @@
+package encapsulationInheritancePolymorphism.polymorphism.enhanced;
+
+public class Engine {
+    private int power = 100;
+
+    public int getPower() {
+        return power;
+    }
+}

src/encapsulationInheritancePolymorphism/polymorphism/enhanced/FuelEngine.java

@@ -0,0 +1,10 @@
+package encapsulationInheritancePolymorphism.polymorphism.enhanced;
+
+public class FuelEngine extends Engine {
+    private String fuelType;
+
+    /*public int getPower() {
+        return 50;
+    }*/
+
+}

src/encapsulationInheritancePolymorphism/polymorphism/enhanced/Main.java

@@ -0,0 +1,28 @@
+package encapsulationInheritancePolymorphism.polymorphism.enhanced;
+
+/*import encapsulationInheritancePolymorphism.inheritance.ElectricEngine;
+import encapsulationInheritancePolymorphism.inheritance.FuelEngine;*/
+
+public class Main {
+    public static void main(String[] args) {
+        /*encapsulationInheritancePolymorphism.inheritance.*/
+        ElectricEngine electricEngine = new ElectricEngine(); // створення нового об'єкту (екземпляру) класу ElectricEngine
+        /*encapsulationInheritancePolymorphism.inheritance.*/
+        FuelEngine fuelEngine = new FuelEngine();
+
+        Engine engine1 = fuelEngine;
+
+        Engine[] engines = {
+                electricEngine,
+                fuelEngine
+        };
+
+        for (Engine engine : engines) {
+            System.out.println(engine.getPower());
+        }
+
+        /*for (int i = 0; i < engines.length; i++) {
+            System.out.println(engines[i].getPower());
+        }*/
+    }
+}

src/encapsulationInheritancePolymorphism/polymorphism/overload/MyClassForOverloadExample.java

@@ -0,0 +1,17 @@
+package encapsulationInheritancePolymorphism.polymorphism.overload;
+
+public class MyClassForOverloadExample {
+    void myMethod(int a) {
+        System.out.println("Integer: " + a);
+    }
+
+    void myMethod(double a) {
+        System.out.println("Double: " + a);
+    }
+
+    public static void main(String[] args) {
+        MyClassForOverloadExample overload = new MyClassForOverloadExample();
+        overload.myMethod(1);
+        overload.myMethod(0.1);
+    }
+}

src/test/A.java

@@ -0,0 +1,13 @@
+package test;
+
+public class A {
+    /*private*/ int f/* = 3*/;
+
+    public int getF() {
+        return f;
+    }
+
+    public void setF(int f) {
+        this.f = f;
+    }
+}

src/test/Main.java

@@ -0,0 +1,15 @@
+package test;
+
+public class Main {
+    public static void main(String[] args) {
+        A a = new A();
+        System.out.println(a.getF());
+        a.setF(1);
+        System.out.println(a.getF());
+
+        System.out.println(a.f);
+
+        int[] array = {1, 2, 1};
+        System.out.println(array.length);
+    }
+}