added comments

This reverts commit c95a243c84.

.gitignore

@@ -1,2 +0,0 @@
-Rust/lab_1/target
-Rust/lab_2/target

Java/lab_1/lab_1.java

@@ -1,31 +0,0 @@
-import java.util.Scanner;
-
-public class lab_1 {
-    
-    public static int protectedInput(String variableToRead, Scanner input) {
-        do {
-            try {
-                System.out.printf("Enter %s: ", variableToRead);
-                return input.nextInt();
-            } catch (Exception e) {
-                System.out.printf("%s must be an integer.\n", variableToRead.toUpperCase());
-                input.nextLine();
-            }
-        } while (true);
-    }
-
-    public static void main(String[] args) {
-        Scanner input = new Scanner(System.in);
-
-        final int n = protectedInput("n", input);
-        final int m = protectedInput("m", input);
-        final int a = protectedInput("a", input);
-        final int b = protectedInput("b", input);
-
-        input.close();
-
-        final float s = ((float) (b + m) / 2) * (m - b + 1) * (n - a + 1);
-
-        System.out.println("S = " + s);
-    }
-}

Java/lab_1/lab_1.kt

@@ -1,21 +0,0 @@
-fun protectedInput(variableName: String): Int {
-    do {
-        try {
-            print("Enter $variableName: ")
-            return readln().toInt()
-        } catch (e: Exception) {
-            println("${variableName.uppercase()} must be an integer!")
-        }
-    } while (true)
-}
-
-fun main() {
-    val n: Int = protectedInput("n")
-    val m: Int = protectedInput("m")
-    val a: Int = protectedInput("a")
-    val b: Int = protectedInput("b")
-
-    val s: Float = (b + m).toFloat() / 2 * (m - b + 1) * (n - a + 1)
-
-    println("S = $s")
-}

Java/lab_2/lab_2.java

@@ -1,106 +0,0 @@
-import java.util.Scanner;
-
-public class lab_2 {
-
-    public static short protectedInput(String inputPrompt, String errorMessage, Scanner input) {
-        short read_variable;
-
-        do {
-            try {
-                System.out.println();
-                System.out.print(inputPrompt);
-
-                read_variable = input.nextShort();
-                break;
-            } catch (Exception e) {
-                System.out.println(errorMessage);
-                input.nextLine();
-            }
-        } while (true);
-
-        return read_variable;
-    }
-
-    public static String format(int number) {
-        int width = String.valueOf(number).length() + 1;
-        String format = "|%" + width + "d ";
-
-        return format;
-    }
-
-    public static double average(short[] row) {
-        short sum = 0;
-
-        for (short element : row) {
-            sum += element;
-        }
-
-        double result = sum / row.length;
-
-        return result;
-    }
-
-    public static void main(String[] args) {
-        short a, rows = 0, columns = 0;
-        String format;
-
-        Scanner input = new Scanner(System.in);
-
-        a = protectedInput("Input a constant to multipy a matrix by: ",
-                "A constant must be a short-data type integer, try again.", input);
-
-        System.out.println();
-        System.out.println("Input size of the matrix.");
-
-        do {
-            rows = protectedInput("Rows: ",
-                    "A number of rows must be a short-data type integer, try again.", input);
-        } while (rows <= 0);
-
-        do {
-            columns = protectedInput("Columns: ",
-                    "A number of columns must be a short-data type integer, try again.", input);
-        } while (columns <= 0);
-
-        input.close();
-
-        short[][] matrix_B = new short[rows][columns];
-
-        System.out.println();
-        System.out.println("Matrix B:");
-
-        format = format(rows * columns);
-
-        for (short i = 0; i < rows; i++) {
-            for (short j = 0; j < columns; j++) {
-                matrix_B[i][j] = (short) ((i + 1) * (j + 1));
-
-                System.out.printf(format, matrix_B[i][j]);
-            }
-
-            System.out.println("|");
-        }
-
-        System.out.println();
-        System.out.println("Matrix a×B:");
-
-        format = format(rows * columns * a);
-
-        for (short i = 0; i < matrix_B.length; i++) {
-            for (short j = 0; j < matrix_B[i].length; j++) {
-                matrix_B[i][j] *= (short) (a);
-
-                System.out.printf(format, matrix_B[i][j]);
-            }
-
-            System.out.println("|");
-        }
-
-        System.out.println();
-        System.out.println("Averages of each row:");
-
-        for (short[] row : matrix_B) {
-            System.out.println(average(row));
-        }
-    }
-}

Java/lab_3/lab_3.java

@@ -1,58 +0,0 @@
-package OOP.Java.lab_3;
-
-public class lab_3 {
-    static int maxStrLength;
-    static String result;
-    
-    public static void cSubUtil(StringBuilder stringbuilder, int leftBoundary, int rightBoundary) {
-        String string = stringbuilder.toString().toLowerCase().replaceAll("[^a-z]","");
-        // check if the indices lie in the range of string
-        // and also if it is palindrome
-        while (leftBoundary >= 0 && rightBoundary < string.length() && string.toLowerCase().charAt(leftBoundary) == string.toLowerCase().charAt(rightBoundary)) {
-            // expand the boundary
-            leftBoundary--;
-            rightBoundary++;
-        }
-        // if it's length is greater than maxLength update
-        // maxLength and res
-        if (rightBoundary - leftBoundary - 1 >= maxStrLength) {
-            result = string.substring(leftBoundary + 1, rightBoundary);
-            maxStrLength = rightBoundary - leftBoundary - 1;
-        }
-        return;
-    }
-
-    public static int longestPalSubstr(StringBuilder string)
-    {
-        result = "";
-        maxStrLength = 1;
-        // for every index in the string check palindromes
-        // starting from that index
-        for (int i = 0; i < string.length(); i++) {
-            // check for odd length palindromes
-            cSubUtil(string, i, i);
-            // check for even length palindromes
-            cSubUtil(string, i, i + 1);
-        }
-        System.out.println("Longest palindrome substring is: " + compareStrings(string));
-        return compareStrings(string).length();
-    }
-
-    public static String compareStrings(StringBuilder builder) {
-        for (int leftBoundary = 0; leftBoundary <= builder.length(); leftBoundary++) {
-            for (int rightBoundary = builder.length(); leftBoundary >= 0; rightBoundary--) {
-                if (result.equals(builder.substring(leftBoundary, rightBoundary).toString().toLowerCase().replaceAll("[^a-z]",""))) {
-                    return builder.substring(leftBoundary, rightBoundary).toString();
-                }
-            }
-        }
-        return "";
-    }
-
-    public static void main(String[] args) {
-        StringBuilder stringToDetect = new StringBuilder("Eva, can I see bees in a cave?");
-
-        System.out.println("Initial string: " + stringToDetect.toString());
-        System.out.println("Length is: " + longestPalSubstr(stringToDetect));
-    }
-}

Lab3/Lab2/Lab2/Program.cs

@@ -0,0 +1,40 @@
+using System;
+
+public class Laba2
+{
+    public static void Main(string[] args)
+    {
+        const int a = 2;
+        int[,] b = new[,] //створення матриці;
+        {
+             { 1, 2, 8 },
+             { 3, 4, 5 },
+             { 6, 7, 9 }
+        };
+        int rows = b.GetLength(0); //отримання довжини рядків
+        int cols = b.GetLength(1); //отримання довжини стовпців
+       for (int i = 0; i < rows; i++) 
+        {
+            int Avg = 0;
+            for (int j = 0; j < cols; j++)
+            {
+                Console.Write(b[i, j] + " ");      // перебір матриці для обчислення середнього значення рядка
+                Avg += b[i, j];
+            }
+            Avg = Avg / cols;
+            Console.Write($"-average of row is:{Avg};"  );
+            Console.WriteLine(" ");
+          
+        }
+       Console.WriteLine(" ");
+       for (int x = 0; x < rows; x++)
+       {
+           for (int y = 0; y < cols; y++)
+           {
+               Console.Write(b[x, y] * a + " "); //виведення матриці, помноженої на константу
+
+           }
+           Console.WriteLine(" ");
+       }
+    }
+}

Lab3/Lab3/Lab3/Program.cs

@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+
+class Lab3
+{
+    public static void Main(string[] args)
+    {
+        string text = "Вухатий великий синiй слон. Яблуко в саду. Зелене яблуко? Груша. Жовта слива висить у саду!";
+        Console.WriteLine(text );
+
+        // розділяємо текст на окремі речення
+        string[] textSplit = text.Split(new[] { '.', '?', '!' }, StringSplitOptions.RemoveEmptyEntries);
+
+        // обчислюємо кількість слів у кожному реченні та створюємо масив з кількістю слів у реченнях
+        int[] amountOfWords = new int[textSplit.Length];
+        for (int i = 0; i < textSplit.Length; i++)
+        {
+            string[] words = textSplit[i].Trim().Split(' ', StringSplitOptions.RemoveEmptyEntries);
+            amountOfWords[i] = words.Length;
+        }
+
+        // створюємо Dictionary, де ключ - кількість слів у реченні, а значення - речення
+        Dictionary<string, int> sentenceDictionary = new Dictionary<string, int>();
+        for (int i = 0; i < textSplit.Length; i++)
+        {
+            sentenceDictionary.Add(textSplit[i],amountOfWords[i] );
+        }
+        var sortedDict = sentenceDictionary.OrderBy(x => x.Value).ToDictionary(x => x.Key, x => x.Value);
+
+
+        Console.WriteLine(String.Join(";", sortedDict.Keys));
+    }
+}

Lab3/Lab4/Lab4/Program.cs

@@ -0,0 +1,86 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ConsoleApp1
+{
+    class Furniture
+    {
+        // 5 полів
+        private string type;
+        private string material;
+        private string color;
+        private int price;
+        private int amount;
+
+        // конструктор з атрибутами
+        public Furniture(string type, string material, string color, int price, int amount)
+        {
+            this.type = type;
+            this.material = material;
+            this.color = color;
+            this.price = price;
+            this.amount = amount;
+        }
+
+        // методи для повернення атрибутів
+        public string getType()
+        {
+            return type;
+        }
+
+        public string getMaterial()
+        {
+            return material;
+        }
+
+        public string getColor()
+        {
+            return color;
+        }
+
+        public int getPrice()
+        {
+            return price;
+        }
+
+        public int getAmount()
+        {
+            return amount;
+        }
+
+        public static void Main(string[] args)
+        {
+
+            Furniture[] furnitureArr = {
+                new Furniture("шафа", "дерево", "коричневий", 5000, 2),
+                new Furniture("стiл", "скло", "чорний", 3000, 3),
+                new Furniture("лiжко", "метал", "срiблястий", 8000, 1),
+                new Furniture("диван", "тканина", "сiрий", 10000, 2),
+                new Furniture("стiлець", "метал", "синій", 500, 4)
+            };
+
+
+            // Сортування масиву за ціною за зростанням
+            var sorted = furnitureArr.OrderBy(ob => ob.price).ToArray();
+            // Вивести відсортований масив
+            Console.WriteLine("Вiдсортований за цiною (за зростанням):");
+            foreach (Furniture f in sorted)
+            {
+                Console.WriteLine(f.getType() + " - " + f.getPrice() + " грн;");
+            }
+            Console.WriteLine(' ');
+            // Сортування масиву за кількістю за спаданням
+            var sortedReversery = furnitureArr.OrderBy(ob => ob.amount).ToArray().Reverse();
+            // Вивести відсортований масив
+            Console.WriteLine("Вiдсортований за кiлькiстю (за спаданням):");
+            foreach (Furniture f in sortedReversery)
+            {
+                Console.Write($"{f.getType()} - {f.getAmount()}; " );
+            }
+            Console.WriteLine(' ');
+        }
+    }
+}

Lab6/Lab6/Program.cs

@@ -0,0 +1,121 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Formats.Asn1;
+
+// Визначити ієрархію рухомого складу залізничного транспорту.Створити пасажирський потяг.Порахувати загальну чисельність пасажирів і багажу в потязі.
+// Провести сортування вагонів потягу за рівнем комфортності. Знайти вагон в потязі, що відповідає заданому діапазону кількості пасажирів.
+
+
+class Lab6
+{
+    public static void Main(string[] args)
+    {
+        List<Wagons> wagons = new List<Wagons>(); //створюємо лист-список вагонів;                      
+
+        // Додаємо вагони за допомогою класу Wagons;
+        wagons.Add(new Wagons.PassengerWagons("Пасажирський", 100, 100, "Вищий", 10));
+        wagons.Add(new Wagons.PassengerWagons("Пасажирський", 50, 48, "Середнiй", 20));
+        wagons.Add(new Wagons.PassengerWagons("Пасажирський", 20, 15, "Низький", 30));
+        wagons.Add(new Wagons.FreightWagons("Вантажний", 10, 10));
+        wagons.Add(new Wagons.FreightWagons("Вантажний", 20, 20));
+        wagons.Add(new Wagons.FreightWagons("Вантажний", 30, 30));
+
+        
+        Console.WriteLine("Усi вагони:");  //відображення всіх вагонів;
+
+        foreach (Wagons wagon in wagons)
+        {
+            Console.WriteLine(wagon.GetType() + ": " + wagon.GetPassengers() + " пасажирiв(-а), " + wagon.GetBaggage() +
+                              " валiз/контейнерiв, " + wagon.GetComfort() + ", " + wagon.GetAmount() + ";");
+        }
+
+        int amountOfPassangers = 0;  //обчислення загальної кількості пасажирів;
+        foreach (Wagons p in wagons)
+        {
+            amountOfPassangers += p.GetPassengers();
+        }
+
+        var sorted = wagons.OrderByDescending(ob => ob.GetComfort()).ToArray(); //сортування вагонів за рівнем комфорту;
+        
+        Console.WriteLine("\nКiлькiсть пасажирiв у пасажирському вагонi: " + amountOfPassangers + ";");
+        Console.WriteLine("\nВеддiть мiнiмальну кiлькiсть пасажирiв: ");
+        var minPassangers = Convert.ToInt32(Console.ReadLine());
+        Console.WriteLine("Веддiть максимальну кiлькiсть пасажирiв: ");
+        var maxPassangers = Convert.ToInt32(Console.ReadLine());
+        foreach (Wagons t in wagons)
+        {
+            if (t.GetPassengers() != null && t.GetPassengers() >= minPassangers && t.GetPassengers() <= maxPassangers) //пошук вагону за кількістю пасажирів;
+            {
+                Console.Write(t.GetType() + " - " + t.GetPassengers()+"; ");
+            }
+            else
+            {
+                throw (new InvalidOperationException("Немає такого вагону;"));
+                
+            }
+
+        }
+
+    }
+
+    class Wagons
+    {
+        private string type; // тип вагону
+        private int passengers; // кількість пасажирів
+        private int baggage; // кількість багажу в тоннах
+        private string comfort; // рейтиг комфорту вагону
+        private int amount; // кількість вагонів
+
+        public Wagons(string type, int? passengers, int? baggage, string comfort, int amount)   //конструктор вагонів;
+        {
+            this.type = type;
+            this.passengers = Convert.ToInt32(passengers);
+            this.baggage = Convert.ToInt32(baggage);
+            this.comfort = comfort;
+            this.amount = amount;
+        }
+
+        public string GetType()         //геттери атрибутів класу;
+        {
+            return type;
+        }
+
+        public int GetPassengers()
+        {
+            return passengers;
+        }
+
+        public int? GetBaggage()
+        {
+            return baggage;
+        }
+
+        public string GetComfort()
+        {
+            return comfort;
+        }
+
+        public int GetAmount()
+        {
+            return amount;
+        }
+
+        // підклас Пасажирський вагон який наслідує батьківський клас Вагони;
+        public class PassengerWagons : Wagons
+        {
+            public PassengerWagons(string type, int passengers, int baggage, string comfort, int amount) : base(type,
+                passengers, baggage, comfort, amount)
+            {
+            }
+        }
+
+        // підклас Вантажний вагон який наслідує батьківський клас Вагони;
+        public class FreightWagons : Wagons
+        {
+            public FreightWagons(string type, int baggage, int amount) : base(type, null, baggage, null, amount)
+            {
+            }
+        }
+    }
+}

READ ME

@@ -0,0 +1 @@
+Files with lab2,3,4 located in in Lab3. My excuses for confusing you

Rust/lab_1/Cargo.lock

@@ -1,16 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-version = 3
-
-[[package]]
-name = "lab_1"
-version = "0.1.0"
-dependencies = [
- "text_io",
-]
-
-[[package]]
-name = "text_io"
-version = "0.1.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5f0c8eb2ad70c12a6a69508f499b3051c924f4b1cfeae85bfad96e6bc5bba46"

Rust/lab_1/Cargo.toml

@@ -1,16 +0,0 @@
-[package]
-name = "lab_1"
-version = "0.1.0"
-edition = "2021"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[profile.release]
-opt-level = 'z'     # Optimize for size
-lto = true          # Enable link-time optimization
-codegen-units = 1   # Reduce number of codegen units to increase optimizations
-panic = 'abort'     # Abort on panic
-strip = true        # Strip symbols from binary*
-
-[dependencies]
-text_io = "0.1.12"

Rust/lab_1/src/main.rs

@@ -1,22 +0,0 @@
-fn protected_read(variable_name: &str) -> i32 {
-    use text_io::try_read;
-    loop {
-        print!("Enter {}: ", variable_name);
-        let read_result: Result<i32, _> = try_read!();
-        match read_result {
-            Ok(read_integer) => return read_integer,
-            Err(_e) => println!("{} must be an integer!", variable_name.to_uppercase()),
-        }
-    }
-}
-
-fn main() {
-    let n: i32 = protected_read("n");
-    let m: i32 = protected_read("m");
-    let a: i32 = protected_read("a");
-    let b: i32 = protected_read("b");
-
-    let s: f32 = ((b + m) as f32 / 2f32) * ((m - b + 1) * (n - a + 1)) as f32;
-
-    println!("S = {}", s);
-}

Rust/lab_2/Cargo.lock

@@ -1,7 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-version = 3
-
-[[package]]
-name = "lab_2"
-version = "0.1.0"

Rust/lab_2/Cargo.toml

@@ -1,8 +0,0 @@
-[package]
-name = "lab_2"
-version = "0.1.0"
-edition = "2021"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]

Rust/lab_2/src/main.rs

@@ -1,3 +0,0 @@
-fn main() {
-    println!("Hello, world!");
-}

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/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);
+    }
+}