diff --git a/lab2/src/main/java/ru/spbstu/telematics/java/App.java b/lab2/src/main/java/ru/spbstu/telematics/java/App.java
index 175d192..261d6c7 100644
--- a/lab2/src/main/java/ru/spbstu/telematics/java/App.java
+++ b/lab2/src/main/java/ru/spbstu/telematics/java/App.java
@@ -5,8 +5,8 @@ public class App
     public static void main( String[] args )
     {
         MyTreeSet<Integer> tree = new MyTreeSet<>();
-        tree.add(10);
-        tree.add(20);
-        tree.add(5);
+        System.out.println(tree.add(10));
+        System.out.println(tree.add(20));
+        System.out.println(tree.add(10));
     }
 }
diff --git a/lab2/src/main/java/ru/spbstu/telematics/java/MyTreeSet.java b/lab2/src/main/java/ru/spbstu/telematics/java/MyTreeSet.java
index 768aee6..af0c31e 100644
--- a/lab2/src/main/java/ru/spbstu/telematics/java/MyTreeSet.java
+++ b/lab2/src/main/java/ru/spbstu/telematics/java/MyTreeSet.java
@@ -19,10 +19,10 @@ public class MyTreeSet<E extends Comparable<E>> {
         root = null;
     }
 
-    public void add(E element) {
+    public boolean add(E element) {
         if (root == null) {
             root = new Node(element);
-            return;
+            return true;
         }
 
         Node currentNode = root;
@@ -31,7 +31,7 @@ public class MyTreeSet<E extends Comparable<E>> {
         while (currentNode != null) {
             int cmp = element.compareTo(currentNode.value);
             if (cmp == 0) {
-                return;
+                return false;
             } 
             parentNode = currentNode;
             currentNode = cmp < 0 ? currentNode.left : currentNode.right;
@@ -44,5 +44,7 @@ public class MyTreeSet<E extends Comparable<E>> {
         } else {
             parentNode.right = newNode;
         }
+
+        return true;
     }
 }