diff --git a/EntityWithRollers.java b/EntityWithRollers.java
index 09ff219..ccc3c89 100644
--- a/EntityWithRollers.java
+++ b/EntityWithRollers.java
@@ -1,41 +1,44 @@
+import java.util.ArrayList;
 import java.util.Random;
 
 public class EntityWithRollers<T extends EntityTracktor, U extends IDrawningRollers> {
     static Random rnd = new Random();
-    private Object[] entities;
-    public int entitiesCount = 0;
-    private Object[] rollers;
-    public int rollersCount = 0;
+    private ArrayList<T> entities;
+    private ArrayList<U> rollers;
+
+    public int maxEntitiesCount = 0;
+    public int maxRollersCount = 0;
 
     public EntityWithRollers(int count) {
-        //new T[count] не работает "Type parameter 'T' cannot be instantiated directly"
-        entities = new Object[count];
-        //new U[count] не работает "Type parameter 'U' cannot be instantiated directly"
-        rollers = new Object[count];
+        entities = new ArrayList<T>();
+        rollers = new ArrayList<U>();
+        maxEntitiesCount = count;
+        maxRollersCount = count;
     }
 
     public boolean add(T entity) {
-        if (entitiesCount >= entities.length) {
+        if (entities.size() >= maxEntitiesCount){
             return false;
         }
-        entities[entitiesCount++] = entity;
+        entities.add(entity);
         return true;
     }
 
     public boolean add(U roller) {
-        if (rollersCount >= rollers.length) {
+        if (rollers.size() >= maxRollersCount){
             return false;
         }
-        rollers[rollersCount++] = roller;
+        rollers.add(roller);
         return true;
     }
 
     public IDrawningObject constructTracktor() {
-        if (entitiesCount == 0 || rollersCount == 0) {
+        if (entities.size() == 0 || rollers.size() == 0) {
             return null;
         }
-        EntityTracktor entity = (EntityTracktor) entities[rnd.nextInt(0, entitiesCount)];
-        IDrawningRollers roller = (IDrawningRollers) rollers[rnd.nextInt(0, rollersCount)];
+
+        EntityTracktor entity = (EntityTracktor) entities.get(rnd.nextInt(0, entities.size()));
+        IDrawningRollers roller = (IDrawningRollers) rollers.get(rnd.nextInt(0, rollers.size()));
 
         if (entity instanceof EntityTrackedVehicle advancedEntity) {
             return new DrawningObjectExcavator(new DrawningTrackedVehicle(advancedEntity, roller));