diff --git a/.idea/misc.xml b/.idea/misc.xml
index eb8da6d..125614e 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_22" default="true" project-jdk-name="openjdk-19" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_22_PREVIEW" project-jdk-name="openjdk-19" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>
\ No newline at end of file
diff --git a/src/L24.java b/src/L24.java
new file mode 100644
index 0000000..ad466d7
--- /dev/null
+++ b/src/L24.java
@@ -0,0 +1,34 @@
+import utils.BinNode;
+
+public class L24 extends Main {
+
+    public static void printAll(BinNode<Integer> root) {
+        printAll(root, 0);
+    }
+
+    public static void printAll(BinNode<Integer> root, int n){
+        if (root != null) {
+            if (isLeaf(root)) {
+                System.out.println(root.getValue() + n * 10);
+            } else {
+                n = n*10 + root.getValue();
+                if (root.hasLeft()) {
+                    printAll(root.getLeft(), n);
+                }
+                if (root.hasRight()) {
+                    printAll(root.getRight(), n);
+                }
+            }
+        }
+    }
+
+
+
+    public static void main(String[] args) {
+        BinNode<Integer> root = buildTree(10);
+        printMeTree(root);
+        printAll(root);
+
+    }
+
+}
diff --git a/src/Test1B.png b/src/Test1B.png
new file mode 100644
index 0000000..5d74ec0
Binary files /dev/null and b/src/Test1B.png differ
diff --git a/src/classes/Card.java b/src/classes/Card.java
new file mode 100644
index 0000000..231eb89
--- /dev/null
+++ b/src/classes/Card.java
@@ -0,0 +1,4 @@
+package classes;
+
+public record Card(String color, int num) {
+}
diff --git a/src/classes/MyBaseA.java b/src/classes/MyBaseA.java
new file mode 100644
index 0000000..31808e0
--- /dev/null
+++ b/src/classes/MyBaseA.java
@@ -0,0 +1,66 @@
+package classes;
+
+import utils.HelpCommands;
+import utils.Node;
+
+public class MyBaseA {
+
+    private Node<Integer> first;
+    private Node<Integer> last;
+
+    public MyBaseA() {
+        this.first = null;
+    }
+
+    public void insert(int x) {
+        if (first == null) {
+            this.first = new Node<>(x);
+        }
+        if (x > first.getValue()) {
+            this.first = new Node<>(x, this.first);
+        } else {
+            Node<Integer> temp = first;
+            while (temp.getNext() != null) {
+                if (x > temp.getNext().getValue()) {
+                    temp.setNext(new Node<>(x, temp.getNext()));
+                }
+            }
+        }
+
+        this.last = HelpCommands.getLast(first);
+    }
+
+    public boolean exists(int x) {
+        Node<Integer> temp = first;
+        while (temp != null) {
+            if (temp.getValue() == x) {
+                return true;
+            }
+            temp = temp.getNext();
+        }
+        return false;
+    }
+
+    public Node<Integer> showMin() {
+        return last;
+    }
+
+    public int getMax() {
+        int max = first.getValue();
+        this.first = first.getNext();
+        return max;
+    }
+
+    public String toString() {
+        String str = "[";
+        Node<Integer> pos = this.first;
+        while (pos != null) {
+            str = str + pos.getValue().toString();
+            if (pos.getNext() != null)
+                str = str + " , ";
+            pos = pos.getNext();
+        }
+        str = str + "]";
+        return str;
+    }
+}
diff --git a/src/classes/MyBaseB.java b/src/classes/MyBaseB.java
new file mode 100644
index 0000000..8bc92b9
--- /dev/null
+++ b/src/classes/MyBaseB.java
@@ -0,0 +1,64 @@
+package classes;
+
+import utils.HelpCommands;
+import utils.Node;
+
+public class MyBaseB {
+
+    private Node<Integer> first;
+    private Node<Integer> last;
+
+    private int div7;
+
+    public MyBaseB() {
+        this.first = null;
+    }
+
+    public void insert(int x) {
+        if (x % 7 == 0) {
+            div7++;
+        }
+        if (first == null) {
+            this.first = new Node<>(x);
+        }
+        if (x > first.getValue()) {
+            this.first = new Node<>(x, this.first);
+        } else {
+            Node<Integer> temp = first;
+            while (temp.getNext() != null) {
+                if (x > temp.getNext().getValue()) {
+                    temp.setNext(new Node<>(x, temp.getNext()));
+                }
+            }
+        }
+
+        this.last = HelpCommands.getLast(first);
+    }
+
+    public int getMax() {
+        int max = first.getValue();
+        this.first = first.getNext();
+        if (max % 7 == 0) {
+            div7--;
+        }
+        return max;
+    }
+
+    public boolean div7(){
+        return div7 > 0;
+    }
+
+    public String toString() {
+        String str = "[";
+        Node<Integer> pos = this.first;
+        while (pos != null) {
+            str = str + pos.getValue().toString();
+            if (pos.getNext() != null)
+                str = str + " , ";
+            pos = pos.getNext();
+        }
+        str = str + "]";
+        return str;
+    }
+
+}
diff --git a/src/classes/kaufmanIsTheGoart.java b/src/classes/kaufmanIsTheGoart.java
new file mode 100644
index 0000000..66d1518
--- /dev/null
+++ b/src/classes/kaufmanIsTheGoart.java
@@ -0,0 +1,12 @@
+package classes;
+
+import utils.BinNode;
+
+public void main() {
+}
+
+public static BinNode<Integer> buildTree(int[] preorder, int[] inorder) {
+    int i = 0;
+    BinNode<Integer> tree = new BinNode<>(preorder[i]);
+        
+}
\ No newline at end of file
diff --git a/src/utils/HelpCommands.java b/src/utils/HelpCommands.java
index 1440b72..217951c 100644
--- a/src/utils/HelpCommands.java
+++ b/src/utils/HelpCommands.java
@@ -646,6 +646,20 @@ public static <T> void addLast(Node<T> node, T value) {
         node.setValue(value);
     }
 
+    public static <T> Node<T> getLast(Node<T> node){
+        while (node.getNext() != null) {
+            node = node.getNext();
+        }
+        return node;
+    }
+
+    public static <T> void setByIndex(Node<T> node, T value, int index){
+        for (int i = 0; i < index - 1; i++) {
+            node = node.getNext();
+        }
+        node.setNext(new Node<>(value, node.getNext()));
+    }
+
     public static BinNode<Integer> buildBinNode(int n) {
         BinNode<Integer> root = new BinNode<Integer>((int) (Math.random() * 99) + 1);
         BinNode<Integer> bn = root;