diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..35eb1dd
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/src/Main.java b/src/Main.java
index 930198c..9db5d88 100644
--- a/src/Main.java
+++ b/src/Main.java
@@ -11,5 +11,25 @@ public static void main(String[] args) {
             // for you, but you can always add more by pressing <shortcut actionId="ToggleLineBreakpoint"/>.
             System.out.println("i = " + i);
         }
+
+        boolean result = isUnique("always");
+        System.out.println(result);
+    }
+
+    public static boolean isUnique(String word) {
+        private CharTreeNode add(CharTreeNode root, char value){
+            if (root == null) {
+                root = new CharTreeNode(value);
+            }else if (value <= root.data) {
+                root.left = add(root.left, value);
+            }else {
+                root.right = add(root.right, value);
+            }
+            return root;
+            }
+        private boolean contains(CharTreeNode root, char value){
+            return root != null && (root.data == value || (value < roo.data && contains (root.left, value)) || (value >= root.data && contains(root.left, value)));
+        }
+        return false;
     }
 }
\ No newline at end of file