Homework1/OOP_Basic is ready

src/main/java/core/basesyntax/MainApp.java

@@ -1,5 +1,54 @@
 package core.basesyntax;
 
+abstract class Machine {
+    public abstract void doWork();
+    public abstract void stopWork();
+}
+
+class Truck extends Machine {
+    @Override
+    public void doWork() {
+        System.out.println("Truck started its work");
+    }
+
+    @Override
+    public void stopWork() {
+        System.out.println("Truck stopped its work");
+    }
+}
+
+class Bulldozer extends Machine {
+    @Override
+    public void doWork() {
+        System.out.println("Bulldozer started its work");
+    }
+
+    @Override
+    public void stopWork() {
+        System.out.println("Bulldozer stopped its work");
+    }
+}
+
+class Excavator extends Machine {
+    @Override
+    public void doWork() {
+        System.out.println("Excavator started its work");
+    }
+
+    @Override
+    public void stopWork() {
+        System.out.println("Excavator stopped its work");
+    }
+}
 public class MainApp {
+    public static void main(String[] args) {
+        Machine[] machines = {new Truck(), new Bulldozer(), new Excavator()};
 
+        for (Machine machine : machines) {
+            machine.doWork();
+            machine.stopWork();
+        }
+    }
 }
+
+