From 51b0e0da0d20f077949874e82b78c07e110e7504 Mon Sep 17 00:00:00 2001
From: jmakho01 <210610870+jmakho01@users.noreply.github.com>
Date: Thu, 12 Feb 2026 14:49:33 -0800
Subject: [PATCH 1/4] Implemented TreeNode traversals

---
 src/Traversal.java | 38 ++++++++++++++++++++++++++++++++++++++
 src/TreeNode.java  |  9 ++++++++-
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/src/Traversal.java b/src/Traversal.java
index 8da0f79..08176b7 100644
--- a/src/Traversal.java
+++ b/src/Traversal.java
@@ -1,5 +1,43 @@
 public class Traversal {
   public static void main(String[] args) {
+    TreeNode root = new TreeNode(10, null, null);
 
+    root.left = new TreeNode(9, null, null);
+    root.left.left = new TreeNode(5, null, null);
+    root.left.right = new TreeNode(2, null, null);
+
+    root.right = new TreeNode(15, null, null);
+    root.right.left = new TreeNode(-3, null, null);
+    root.right.right = new TreeNode(5, null, null);
+    root.right.right.right = new TreeNode(22, null, null);
+
+    //preOrder(root);
+    postOrder(root);
+  }
+
+  // print a tree rooted at the given node in pre-order
+  public static void preOrder(TreeNode node) {
+    //if null, return
+    if (node == null) { return; }
+    //print value
+    System.out.println(node.value);
+    //traverse left
+    preOrder(node.left);
+    //traverse right
+    preOrder(node.right);
   }
+
+  public static void postOrder(TreeNode node) {
+    if (node == null) { return; }
+    postOrder(node.left);
+    postOrder(node.right);
+    System.out.println(node.value);
+  }
+
+  public static void inOrder(TreeNode node) {
+    if (node == null) { return; }
+    inOrder(node.left);
+    System.out.println(node.value);
+    inOrder(node.right);
+    }
 }
diff --git a/src/TreeNode.java b/src/TreeNode.java
index acd9639..a2959d4 100644
--- a/src/TreeNode.java
+++ b/src/TreeNode.java
@@ -1,4 +1,11 @@
 public class TreeNode {
+    public int value;
+    public TreeNode left;
+    public TreeNode right;
 
-  
+    public TreeNode(int value, TreeNode left, TreeNode right) {
+        this.value = value;
+        this.left = left;
+        this.right = right;
+    }
 }
\ No newline at end of file

From ff1cd4d3b30fe9612155a76ecce72f669a9cf9d4 Mon Sep 17 00:00:00 2001
From: jmakho01 <210610870+jmakho01@users.noreply.github.com>
Date: Tue, 17 Feb 2026 14:36:43 -0800
Subject: [PATCH 2/4] Implemented generic class and added additional methods

---
 src/Traversal.java | 56 +++++++++++++++++++++++++++++++++++-----------
 src/TreeNode.java  | 10 ++++-----
 2 files changed, 48 insertions(+), 18 deletions(-)

diff --git a/src/Traversal.java b/src/Traversal.java
index 08176b7..989f828 100644
--- a/src/Traversal.java
+++ b/src/Traversal.java
@@ -1,22 +1,52 @@
 public class Traversal {
   public static void main(String[] args) {
-    TreeNode root = new TreeNode(10, null, null);
+    TreeNode<Integer> root = new TreeNode<Integer>(10, null, null);
 
-    root.left = new TreeNode(9, null, null);
-    root.left.left = new TreeNode(5, null, null);
-    root.left.right = new TreeNode(2, null, null);
+    root.left = new TreeNode<Integer>(9, null, null);
+    root.left.left = new TreeNode<Integer>(5, null, null);
+    root.left.right = new TreeNode<Integer>(2, null, null);
 
-    root.right = new TreeNode(15, null, null);
-    root.right.left = new TreeNode(-3, null, null);
-    root.right.right = new TreeNode(5, null, null);
-    root.right.right.right = new TreeNode(22, null, null);
+    root.right = new TreeNode<Integer>(15, null, null);
+    root.right.left = new TreeNode<Integer>(-3, null, null);
+    root.right.right = new TreeNode<Integer>(5, null, null);
+    root.right.right.right = new TreeNode<Integer>(22, null, null);
+
+    TreeNode<String> stringRoot = new TreeNode<String>("hello", null, null);
+
+    stringRoot.left = new TreeNode<String>("how", null, null);
+    stringRoot.left.left = new TreeNode<String>("are", null, null);
+    stringRoot.left.right = new TreeNode<String>("you", null, null);
+
+    stringRoot.right = new TreeNode<String>("I", null, null);
+    stringRoot.right.left = new TreeNode<String>("am", null, null);
+    stringRoot.right.right = new TreeNode<String>("so", null, null);
+    stringRoot.right.right.right = new TreeNode<String>("good", null, null);
 
     //preOrder(root);
-    postOrder(root);
+    //postOrder(root);
+    //inOrder(stringRoot);
+    //printGreater(root, 7);
+
+    System.out.println(countNodes(root));
+  }
+
+  public static int countNodes(TreeNode<?> node) {
+    return node == null ? 0 : countNodes(node.left) + countNodes(node.right) + 1;
+    //int leftCount = countNodes(node.left);
+    //int rightCount = countNodes(node.right);
+    //int overallCount = leftCount + rightCount + 1;
+    //return overallCount;
+  }
+
+  public static void printGreater(TreeNode<Integer> node, int threshold) {
+    if (node == null) return;
+    if (node.value > threshold) System.out.println(node.value);
+    printGreater(node.left, threshold);
+    printGreater(node.right, threshold);
   }
 
   // print a tree rooted at the given node in pre-order
-  public static void preOrder(TreeNode node) {
+  public static void preOrder(TreeNode<?> node) {
     //if null, return
     if (node == null) { return; }
     //print value
@@ -27,17 +57,17 @@ public static void preOrder(TreeNode node) {
     preOrder(node.right);
   }
 
-  public static void postOrder(TreeNode node) {
+  public static <T> void postOrder(TreeNode<T> node) {
     if (node == null) { return; }
     postOrder(node.left);
     postOrder(node.right);
     System.out.println(node.value);
   }
 
-  public static void inOrder(TreeNode node) {
+  public static <E> void inOrder(TreeNode<E> node) {
     if (node == null) { return; }
     inOrder(node.left);
     System.out.println(node.value);
     inOrder(node.right);
-    }
+  }
 }
diff --git a/src/TreeNode.java b/src/TreeNode.java
index a2959d4..7d311f0 100644
--- a/src/TreeNode.java
+++ b/src/TreeNode.java
@@ -1,9 +1,9 @@
-public class TreeNode {
-    public int value;
-    public TreeNode left;
-    public TreeNode right;
+public class TreeNode<T> {
+    public T value;
+    public TreeNode<T> left;
+    public TreeNode<T> right;
 
-    public TreeNode(int value, TreeNode left, TreeNode right) {
+    public TreeNode(T value, TreeNode<T> left, TreeNode<T> right) {
         this.value = value;
         this.left = left;
         this.right = right;

From 248dbd08078c4fcd9c52ca0a7e47c5f0ca7c779d Mon Sep 17 00:00:00 2001
From: jmakho01 <210610870+jmakho01@users.noreply.github.com>
Date: Thu, 19 Feb 2026 14:31:10 -0800
Subject: [PATCH 3/4] Implemented toMap method

---
 src/Traversal.java | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/Traversal.java b/src/Traversal.java
index 989f828..7812f2d 100644
--- a/src/Traversal.java
+++ b/src/Traversal.java
@@ -1,3 +1,6 @@
+import java.util.Map;
+import java.util.HashMap;
+
 public class Traversal {
   public static void main(String[] args) {
     TreeNode<Integer> root = new TreeNode<Integer>(10, null, null);
@@ -26,8 +29,22 @@ public static void main(String[] args) {
     //postOrder(root);
     //inOrder(stringRoot);
     //printGreater(root, 7);
+    //System.out.println(countNodes(root));
+
+    System.out.println(toMap(stringRoot));
+  }
+
+  public static <T> Map<T,Integer> toMap(TreeNode<T> node) {
+      Map<T, Integer> counts = new HashMap<>();
+      toMap(node, counts);
+      return counts;
+  }
 
-    System.out.println(countNodes(root));
+  private static <T> void toMap(TreeNode<T> node, Map<T, Integer> counts) {
+      if(node == null) { return; }
+      counts.put(node.value, counts.getOrDefault(node.value, 0) + 1);
+      toMap(node.left, counts);
+      toMap(node.right, counts);
   }
 
   public static int countNodes(TreeNode<?> node) {

From 89e9d60908b2139f14e1093b0e6b3472ffef56e2 Mon Sep 17 00:00:00 2001
From: jmakho01 <210610870+jmakho01@users.noreply.github.com>
Date: Tue, 24 Feb 2026 14:50:19 -0800
Subject: [PATCH 4/4] Implemented preOrderIter() and levelOrder() methods

---
 src/Traversal.java | 67 ++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 59 insertions(+), 8 deletions(-)

diff --git a/src/Traversal.java b/src/Traversal.java
index 7812f2d..9b05f02 100644
--- a/src/Traversal.java
+++ b/src/Traversal.java
@@ -1,5 +1,8 @@
 import java.util.Map;
 import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.Stack;
+import java.util.Queue;
 
 public class Traversal {
   public static void main(String[] args) {
@@ -25,26 +28,74 @@ public static void main(String[] args) {
     stringRoot.right.right = new TreeNode<String>("so", null, null);
     stringRoot.right.right.right = new TreeNode<String>("good", null, null);
 
+    TreeNode<Integer> megaRoot = new TreeNode<Integer>(1, null, null);
+
+    TreeNode<Integer> current = megaRoot;
+
+    for(int i = 2; i <= 50000; i++) {
+      current.right = new TreeNode<Integer> (i, null, null);
+      current = current.right;
+    }
+
+    levelOrder(root);
+
+    //preOrderIter(megaRoot);
+
+    //System.out.println("Preorder recursive");
     //preOrder(root);
+    //System.out.println("Preorder iterative");
+    //preOrderIter(root);
+
     //postOrder(root);
     //inOrder(stringRoot);
     //printGreater(root, 7);
     //System.out.println(countNodes(root));
+    //System.out.println(toMap(stringRoot));
+  }
+
+  public static <T> void preOrderIter(TreeNode<T> node) {
+    Stack<TreeNode<T>> stack = new Stack<>();
+
+    stack.push(node);
+
+    while(!stack.empty()) {
+      TreeNode<T> current = stack.pop();
+
+      if(current == null) { continue; }
+
+      System.out.println(current.value);
+      stack.push(current.right);
+      stack.push(current.left);
+    }
+  }
+
+  public static <T> void levelOrder(TreeNode<T> node) {
+    Queue<TreeNode<T>> queue = new LinkedList<>();
+
+    queue.add(node);
+
+    while(!queue.isEmpty()) {
+      TreeNode<T> current = queue.poll();
+
+      if(current == null) { continue; }
 
-    System.out.println(toMap(stringRoot));
+      System.out.println(current.value);
+      queue.add(current.left);
+      queue.add(current.right);
+    }
   }
 
   public static <T> Map<T,Integer> toMap(TreeNode<T> node) {
-      Map<T, Integer> counts = new HashMap<>();
-      toMap(node, counts);
-      return counts;
+    Map<T, Integer> counts = new HashMap<>();
+    toMap(node, counts);
+    return counts;
   }
 
   private static <T> void toMap(TreeNode<T> node, Map<T, Integer> counts) {
-      if(node == null) { return; }
-      counts.put(node.value, counts.getOrDefault(node.value, 0) + 1);
-      toMap(node.left, counts);
-      toMap(node.right, counts);
+    if(node == null) { return; }
+    counts.put(node.value, counts.getOrDefault(node.value, 0) + 1);
+    toMap(node.left, counts);
+    toMap(node.right, counts);
   }
 
   public static int countNodes(TreeNode<?> node) {