update: traverse InOrder

BinaryTree.java

@@ -118,6 +118,7 @@ public class BinaryTree {
 
   public void traversePreOrder(Node node) {
     if (node != null) {
+      // NLR
       System.out.print(" " + node.getContent());
       traversePreOrder(node.getLeftNode());
       traversePreOrder(node.getRightNode());
@@ -126,12 +127,22 @@ public class BinaryTree {
 
   public void traversePostOrder(Node node) {
     if (node != null) {
+      // LRN
       traversePostOrder(node.getLeftNode());
       traversePostOrder(node.getRightNode());
       System.out.print(" " + node.getContent());
     }
   }
 
+  public void traverseInOrder(Node node) {
+    if (node != null) {
+      // LNR
+      traverseInOrder(node.getLeftNode());
+      System.out.print(" " + node.getContent());
+      traverseInOrder(node.getRightNode());
+    }
+  }
+
   // Print functions from https://www.baeldung.com/java-print-binary-tree-diagram
   // public void print() {
   //   StringBuilder sb = new StringBuilder();

Main.java

@@ -25,6 +25,12 @@ public class Main {
         // binaryTree.remove(72);
         // binaryTree.remove(42);
 
+        System.out.println("------ TRAVERSE ------");
+        System.out.print(" [Post Order]:");
         binaryTree.traversePostOrder(binaryTree.getRoot());
-    }
+        System.out.print("\n [Pre Order]: ");
+        binaryTree.traversePreOrder(binaryTree.getRoot());
+        System.out.print("\n [In Order]:  ");
+        binaryTree.traverseInOrder(binaryTree.getRoot());
+    } 
 }