5. принимает массив байт, если в массиве есть повторяющиеся елементы, возвращает тру

DecToBin

public class DecToBinary {
    String getBinary(int number, int outputLength){
        if (number==0){
            return "0";
        }
        String strNumber = "";
        while (!((number/2==0)&&(number%2==1))){
            strNumber = (number % 2) + strNumber;
            number = number / 2;
        }
        strNumber = (number % 2) + strNumber;
        //strNumber = String.format("%16s", Integer.toBinaryString(strNumber)).replace(' ', '0')
        return strNumber;
    }
}

EmployeeService

import java.util.Random;

class EmployeeService {
    Employee[] users;

    void generateEmployees(int size) {
        String[] maleNames = {"Anatoliy","Oleg","Vladimir","Yuriy"};
        String[] femaleNames = {"Anna","Olha","Vlada","Yulia"};

        Random random = new Random();
        users = new Employee[size];
        // generate random users
        // [1, "Tolik", 1000, 'M']
        for (int i = 0; i < users.length; i++) {
            users[i] = new Employee();
            users[i].age = random.nextInt(65-18+1)+18;
            users[i].gender = users[i].age % 2==0 ? 'M' : 'F';
            users[i].salary = random.nextInt(3000-500+1)+500;

            String personName = maleNames[random.nextInt(maleNames.length)];
            if (users[i].gender == 'F') {
                personName = femaleNames[random.nextInt(femaleNames.length)];
            }
            users[i].name = personName;
        }

    }

    // print all users in array
    void print() {
        for (int i = 0; i < users.length; i++) {
            System.out.println( "Name: "+users[i].name+
                                "; Gender: " + users[i].gender +
                                "; Age: " + users[i].age +
                                "; Salary: " + users[i].salary);
        }

    }

    // ASC
    void sortByName() {
        for (int i = 0; i < users.length; i++) {
            for (int i = 0; i < users.length; i++) {
        }
    }

    // if names are equal, compare by salary
    void sortByNameAndSalary() {

    }

    // return sum of all salaries
    double calculateSalary() {
        return 0;
    }

    Employee[] searchByName(String name) {
        return null;
    }

}

ex5

public class Duplicates {

    public static void main(String[] args) {
        byte[] startArray = {-10,-128,127,1,5,55,-10};
        boolean isDuplicates = isDuplictesInArray(startArray);
        System.out.println(isDuplicates);
    }

    static boolean isDuplictesInArray(byte[] arrayVal){
        byte[] additionalArray = new byte[256];

        for (int i=0;i<arrayVal.length;i++){
            if (additionalArray[arrayVal[i]+128] == 1){
                return true;
            }
            else{
                additionalArray[arrayVal[i]+128] = 1;
            }
        }

        return false;
    }
}

Fridge

public class Fridge {
    public int[][] tumblers = new int[4][4];

    void initialFill(String variant){
        int x = 0, y = 0;
        for (int i = 0; i < variant.length(); i++) {
            tumblers[x][y] = Integer.parseInt(variant.substring(i,i+1));
            if (((i+1)%4==0)&&(i!=0)){
                x++;
                y=0;
            }
            else {
                y++;
            }
        }
    }

    void printArray(){
        for (int i = 0; i < tumblers.length; i++) {
            for (int j = 0; j < tumblers[i].length; j++) {
                System.out.print(tumblers[i][j]);
            }
            System.out.println();
        }
    }

    void turnLinked(int x, int y){
        int newValue = tumblers[x][y]==0?1:0;

        for (int i = 0; i < tumblers.length; i++) {
            for (int j = 0; j < tumblers[i].length; j++) {
                if ((i == x) || (j == y)) {
                    tumblers[i][j] = newValue;
                }
            }
        }
    }
}

LinkedStack

class LinkedStack {
    Node head;
    int size;

    Node getLastNode(Node node){
        if (node.next != null){
            return getLastNode(node.next);
        }
        return node;
    }

    // same methods as in ArrayStack
    void push(Object value) {
        //getLastNode(head).value = value;
        //getLastNode(head).next = new Node();

        if (head == null){
            head = new Node();
            head.value = value;
        }
        else {
            Node bufferNode = head;
            Node parentNode = head;
            for (int i = 0; i < size; i++) {
                parentNode = bufferNode;
                bufferNode = bufferNode.next;
            }
            bufferNode = new Node();
            bufferNode.value = value;
            parentNode.next = bufferNode;
        }

        size++;
    }

    Object poll() {
        size--;

        Node lastNode = getLastNode(head);

        Node parentNode = head;
        for (int i = 0; i < size-1; i++) {
            parentNode = parentNode.next;
        }

        parentNode.next = null;

        return lastNode.value;
    }

    Object peek() {
        return getLastNode(head).value;
    }

    int size() {
        return size;
    }
}

Test

public class Test {
    public static void main(String[] args) {
        LinkedStack linkedStack = new LinkedStack();
        linkedStack.push("A");
        linkedStack.push(32);
        linkedStack.push(8.0);
        linkedStack.push('R');
        System.out.println("Size:" + linkedStack.size());
        System.out.println("Value peek:" + linkedStack.peek());
        System.out.println("Value pool:" + linkedStack.poll());
        System.out.println("Value peek:" + linkedStack.peek());
        linkedStack.push('C');
        System.out.println("Size:" + linkedStack.size());
        System.out.println("Value peek:" + linkedStack.peek());

    }
}

TestForFridge

public class Test {
    public static void main(String[] args) {

        //DecToBinary dtb = new DecToBinary();
        /*for (int i = 1; i < 65536; i++) {
            String newVariant = String.format("%16s", Integer.toBinaryString(i)).replace(' ', '0');
            Fridge fridge = new Fridge();
            fridge.initialFill(newVariant);
            fridge.printArray();
            System.out.println("----"+i+"-----");
        }*/

        Fridge fridge = new Fridge();
        fridge.initialFill("0000000000000001");
        fridge.printArray();
        fridge.turnLinked(0,0);
        System.out.println("---------");
        fridge.printArray();
        fridge.turnLinked(0,0);
        System.out.println("---------");
        fridge.printArray();

    }
}