diff --git a/src/main/java/school/lemon/changerequest/java/employees/Accountant.java b/src/main/java/school/lemon/changerequest/java/employees/Accountant.java
new file mode 100644
index 0000000..a24e578
--- /dev/null
+++ b/src/main/java/school/lemon/changerequest/java/employees/Accountant.java
@@ -0,0 +1,18 @@
+package school.lemon.changerequest.java.employees;
+
+/**
+ * Created by Yaroslav Pavlinskiy on 06.01.2017.
+ */
+public class Accountant extends Employee {
+    Accountant(String name) {
+        super(name);
+    }
+
+    public double calculateSalaryForEmployee(Employee e) {
+        if(e instanceof Programmer || e instanceof Manager || e instanceof Accountant)
+        {
+            return e.calculateSalary();
+        }
+        return 0;
+    }
+}
diff --git a/src/main/java/school/lemon/changerequest/java/employees/Demo.java b/src/main/java/school/lemon/changerequest/java/employees/Demo.java
new file mode 100644
index 0000000..84bbebd
--- /dev/null
+++ b/src/main/java/school/lemon/changerequest/java/employees/Demo.java
@@ -0,0 +1,25 @@
+package school.lemon.changerequest.java.employees;
+
+/**
+ * Created by Yaroslav Pavlinskiy on 06.01.2017.
+ */
+public class Demo {
+    public static void main(String[] args) {
+        Programmer programmer = new Programmer("Stiv");
+        programmer.setSalary(100);
+        programmer.working(320);
+        System.out.println(programmer);
+
+        Manager manager = new Manager("Bob");
+        manager.setSalary(100);
+        manager.working(320);
+        System.out.println(manager);
+
+        Accountant accountant = new Accountant("Gloria");
+        accountant.setSalary(100);
+        accountant.working(320);
+        System.out.println(accountant);
+
+        System.out.println(accountant.calculateSalaryForEmployee(manager));
+    }
+}
diff --git a/src/main/java/school/lemon/changerequest/java/employees/Employee.java b/src/main/java/school/lemon/changerequest/java/employees/Employee.java
new file mode 100644
index 0000000..6149417
--- /dev/null
+++ b/src/main/java/school/lemon/changerequest/java/employees/Employee.java
@@ -0,0 +1,52 @@
+package school.lemon.changerequest.java.employees;
+
+/**
+ * Created by Yaroslav Pavlinskiy on 06.01.2017.
+ */
+public abstract class Employee {
+    public final int HOURS_PER_MONTH = 160;
+    private String name;
+    private double salary;
+    private int hours;
+
+    Employee(String name)
+    {
+        this.name = name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public double getSalary() {
+        return salary;
+    }
+
+    public int getHours() {
+        return hours;
+    }
+
+    public void setSalary(double salary)
+    {
+        this.salary = salary;
+    }
+
+    public void working(int hours)
+    {
+        this.hours += hours;
+    }
+
+    public double calculateSalary()
+    {
+        if(this.hours >= HOURS_PER_MONTH)
+            return salary;
+        return salary/(HOURS_PER_MONTH/hours);
+    }
+
+    @Override
+    public String toString() {
+        return String.format("%s with salary %s $ worked %s hours -> salary %s $",getName(),getSalary(),getHours(),calculateSalary());
+    }
+
+
+}
diff --git a/src/main/java/school/lemon/changerequest/java/employees/Manager.java b/src/main/java/school/lemon/changerequest/java/employees/Manager.java
new file mode 100644
index 0000000..499fd4e
--- /dev/null
+++ b/src/main/java/school/lemon/changerequest/java/employees/Manager.java
@@ -0,0 +1,10 @@
+package school.lemon.changerequest.java.employees;
+
+/**
+ * Created by Yaroslav Pavlinskiy on 06.01.2017.
+ */
+public class Manager extends Employee {
+    Manager(String name) {
+        super(name);
+    }
+}
diff --git a/src/main/java/school/lemon/changerequest/java/employees/Programmer.java b/src/main/java/school/lemon/changerequest/java/employees/Programmer.java
new file mode 100644
index 0000000..0bd5fce
--- /dev/null
+++ b/src/main/java/school/lemon/changerequest/java/employees/Programmer.java
@@ -0,0 +1,15 @@
+package school.lemon.changerequest.java.employees;
+
+/**
+ * Created by Yaroslav Pavlinskiy on 06.01.2017.
+ */
+public class Programmer extends Employee {
+    Programmer(String name) {
+        super(name);
+    }
+
+    @Override
+    public double calculateSalary() {
+        return (double)getHours()/((double)HOURS_PER_MONTH / getSalary());
+    }
+}
diff --git a/src/main/java/school/lemon/changerequest/java/matrix/Matrix.java b/src/main/java/school/lemon/changerequest/java/matrix/Matrix.java
new file mode 100644
index 0000000..fcfdad1
--- /dev/null
+++ b/src/main/java/school/lemon/changerequest/java/matrix/Matrix.java
@@ -0,0 +1,104 @@
+package school.lemon.changerequest.java.matrix;
+
+/**
+ * Created by Yaroslav Pavlinskiy on 12.12.2016.
+ */
+public class Matrix {
+
+    private final int Rows; // count Rows
+    private final int Columns; // count Columns
+    private final int[][] data; // 2d array for matrix
+
+    public Matrix(int R,int C)// Constructor with Rows and Columns
+    {
+        this.Rows = R;
+        this.Columns = C;
+        this.data = new int[R][C];
+    }
+
+    public Matrix(int[][]data) //Constructor 2d array
+    {
+        this.Rows = data.length;
+        this.Columns = data[0].length;
+        this.data = data;
+    }
+    private Matrix(Matrix A) { this(A.data); }
+
+    public Matrix AddMatrix(Matrix B) // Method that adding matrix A and B
+    {
+        return Calculate(B,'+');
+    }
+
+    public Matrix SubtractMatrix(Matrix B)
+    {
+        return Calculate(B,'-');
+    }
+
+    public Matrix MultiplyNumber(int n)
+    {
+        Matrix A = this;
+        Matrix C = new Matrix(Rows, Columns);
+        for (int i = 0; i < Rows; i++)
+            for (int j = 0; j < Columns; j++)
+                C.data[i][j] = A.data[i][j] * n;
+        return C;
+    }
+
+    public  Matrix MultiplyMatrix(Matrix B)
+    {
+        return Calculate(B,'*');
+    }
+
+    public Matrix Transpose()
+    {
+        Matrix A = this;
+        Matrix C = new Matrix(Rows,Columns);
+        for (int i = 0; i < Rows; i++)
+            for (int j = 0; j < Columns; j++)
+                C.data[i][j] = A.data[j][i];
+        return C;
+    }
+
+    public Matrix Calculate(Matrix B,char d)
+    {
+        Matrix A = this;
+        if (B.Rows != A.Rows || B.Columns != A.Columns) return null;
+        Matrix C = new Matrix(Rows, Columns);
+        switch (d)
+        {
+            case '*':
+                for (int i = 0; i < Rows; i++)
+                    for (int j = 0; j < Columns; j++)
+                        C.data[i][j] = A.data[i][j] * B.data[i][j];
+                break;
+            case '+':
+                for (int i = 0; i < Rows; i++)
+                    for (int j = 0; j < Columns; j++)
+                        C.data[i][j] = A.data[i][j] + B.data[i][j];
+                break;
+            case '-':
+                for (int i = 0; i < Rows; i++)
+                    for (int j = 0; j < Columns; j++)
+                        C.data[i][j] = A.data[i][j] - B.data[i][j];
+                break;
+
+        }
+
+        return C;
+    }
+
+    @Override
+    public String toString() {
+        for(int i = 0; i < Rows;i++)
+        {
+            for(int j = 0; j < Columns;j++)
+            {
+                System.out.print(data[i][j]+" ");
+            }
+            System.out.println();
+        }
+        System.out.println("------------");
+        return "";
+    }
+
+}
diff --git a/src/main/java/school/lemon/changerequest/java/matrix/TestApp.java b/src/main/java/school/lemon/changerequest/java/matrix/TestApp.java
new file mode 100644
index 0000000..de49e53
--- /dev/null
+++ b/src/main/java/school/lemon/changerequest/java/matrix/TestApp.java
@@ -0,0 +1,52 @@
+package school.lemon.changerequest.java.matrix;
+import java.io.*;
+/**
+ * Created by Yaroslav Pavlinskiy on 12.12.2016.
+ */
+public class TestApp {
+
+    public static void main(String[] args) {
+        TestApp app = new TestApp();
+
+        int[][]A = new int[2][2];//initialization matrix A
+        int[][]B = new int[2][2];//initialization matrix
+
+        A[0][0] = 4;
+        A[0][1] = 2;
+        A[1][0] = 9;
+        A[1][1] = 0;
+
+        B[0][0] = 3;
+        B[0][1] = 1;
+        B[1][0] = -3;
+        B[1][1] = 4;
+
+        Matrix a = new Matrix(A);
+        System.out.println("Matrix A:");
+        a.toString();
+
+        Matrix b = new Matrix(B);
+        System.out.println("Matrix B:");
+        b.toString();
+
+        System.out.println("Matrix Add:");
+        a.AddMatrix(b).toString();
+
+        System.out.println("Matrix Subtract:");
+        a.SubtractMatrix(b).toString();
+
+        System.out.println("MultiplayNumber:");
+        a.MultiplyNumber(2).toString();
+
+        System.out.println("MultiplayMatrix:");
+        a.MultiplyMatrix(b).toString();
+
+        System.out.println("Transpose Matrix:");
+        a.Transpose().toString();
+
+
+
+
+
+    }
+}