From 4f6e63bc2b3d790309e8a773f5ae1f751f2c8696 Mon Sep 17 00:00:00 2001
From: PauLopNun <paulopeznunez@gmail.com>
Date: Mon, 6 Oct 2025 02:23:07 +0200
Subject: [PATCH 1/3] Add BinaryTreeSort algorithm
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Implements Binary Tree Sort using BST with inorder traversal
- O(n log n) average case, O(n²) worst case time complexity
- Includes comprehensive test suite extending SortingAlgorithmTest
---
 .../thealgorithms/sorts/BinaryTreeSort.java   | 67 +++++++++++++++++++
 .../sorts/BinaryTreeSortTest.java             |  8 +++
 2 files changed, 75 insertions(+)
 create mode 100644 src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
 create mode 100644 src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java

diff --git a/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java b/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
new file mode 100644
index 000000000000..cafd4bc56e41
--- /dev/null
+++ b/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
@@ -0,0 +1,67 @@
+package com.thealgorithms.sorts;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Binary Tree Sort Algorithm Implementation
+ *
+ * @see <a href="https://en.wikipedia.org/wiki/Tree_sort">Binary Tree Sort Algorithm</a>
+ */
+public class BinaryTreeSort implements SortAlgorithm {
+
+    private static class TreeNode<T extends Comparable<T>> {
+        T data;
+        TreeNode<T> left;
+        TreeNode<T> right;
+
+        TreeNode(T data) {
+            this.data = data;
+            this.left = null;
+            this.right = null;
+        }
+    }
+
+    @Override
+    public <T extends Comparable<T>> T[] sort(T[] array) {
+        if (array == null || array.length <= 1) {
+            return array;
+        }
+        
+        TreeNode<T> root = null;
+        for (T value : array) {
+            root = insert(root, value);
+        }
+
+        List<T> result = new ArrayList<>();
+        inorder(root, result);
+        
+        for (int i = 0; i < array.length; i++) {
+            array[i] = result.get(i);
+        }
+        
+        return array;
+    }
+
+    private <T extends Comparable<T>> TreeNode<T> insert(TreeNode<T> root, T data) {
+        if (root == null) {
+            return new TreeNode<>(data);
+        }
+
+        if (SortUtils.less(data, root.data)) {
+            root.left = insert(root.left, data);
+        } else {
+            root.right = insert(root.right, data);
+        }
+
+        return root;
+    }
+
+    private <T extends Comparable<T>> void inorder(TreeNode<T> root, List<T> result) {
+        if (root != null) {
+            inorder(root.left, result);
+            result.add(root.data);
+            inorder(root.right, result);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java b/src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java
new file mode 100644
index 000000000000..3f7c78435642
--- /dev/null
+++ b/src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java
@@ -0,0 +1,8 @@
+package com.thealgorithms.sorts;
+
+public class BinaryTreeSortTest extends SortingAlgorithmTest {
+    @Override
+    SortAlgorithm getSortAlgorithm() {
+        return new BinaryTreeSort();
+    }
+}
\ No newline at end of file

From aa4c1db45bc4f86bb923e665e323b92ef566b48a Mon Sep 17 00:00:00 2001
From: PauLopNun <paulopeznunez@gmail.com>
Date: Mon, 6 Oct 2025 02:30:52 +0200
Subject: [PATCH 2/3] Fix clang-format: add newlines

---
 src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java     | 2 +-
 src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java b/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
index cafd4bc56e41..0fad04b6e393 100644
--- a/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
+++ b/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
@@ -64,4 +64,4 @@ private <T extends Comparable<T>> void inorder(TreeNode<T> root, List<T> result)
             inorder(root.right, result);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java b/src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java
index 3f7c78435642..b6df22851275 100644
--- a/src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java
+++ b/src/test/java/com/thealgorithms/sorts/BinaryTreeSortTest.java
@@ -5,4 +5,4 @@ public class BinaryTreeSortTest extends SortingAlgorithmTest {
     SortAlgorithm getSortAlgorithm() {
         return new BinaryTreeSort();
     }
-}
\ No newline at end of file
+}

From c3a46ece6dadcf99e1dfe15dff403e878bcacfbc Mon Sep 17 00:00:00 2001
From: PauLopNun <paulopeznunez@gmail.com>
Date: Mon, 6 Oct 2025 02:54:43 +0200
Subject: [PATCH 3/3] Remove trailing spaces from BinaryTreeSort

- Fix checkstyle violations on lines 30, 38, 42
- Remove trailing whitespace for compliance
- No functional changes
---
 src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java b/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
index 0fad04b6e393..edc82abb08ba 100644
--- a/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
+++ b/src/main/java/com/thealgorithms/sorts/BinaryTreeSort.java
@@ -27,7 +27,7 @@ public <T extends Comparable<T>> T[] sort(T[] array) {
         if (array == null || array.length <= 1) {
             return array;
         }
-        
+
         TreeNode<T> root = null;
         for (T value : array) {
             root = insert(root, value);
@@ -35,11 +35,11 @@ public <T extends Comparable<T>> T[] sort(T[] array) {
 
         List<T> result = new ArrayList<>();
         inorder(root, result);
-        
+
         for (int i = 0; i < array.length; i++) {
             array[i] = result.get(i);
         }
-        
+
         return array;
     }