From 4c9fd50d1cf37c29502a444c1c056bba2ec276b8 Mon Sep 17 00:00:00 2001
From: Orkhan Huseynli <orkhan.huseyn@outlook.com>
Date: Sun, 25 Dec 2022 19:34:24 +0400
Subject: [PATCH] Update 104-Maximum-Depth-of-Binary-Tree.java

---
 java/104-Maximum-Depth-of-Binary-Tree.java | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/java/104-Maximum-Depth-of-Binary-Tree.java b/java/104-Maximum-Depth-of-Binary-Tree.java
index 325b5e298..1a2032fd1 100644
--- a/java/104-Maximum-Depth-of-Binary-Tree.java
+++ b/java/104-Maximum-Depth-of-Binary-Tree.java
@@ -1,7 +1,27 @@
+// Recursive DFS
 class Solution {
-
     public int maxDepth(TreeNode root) {
         if (root == null) return 0;
         return 1 + Math.max(maxDepth(root.left), maxDepth(root.right));
     }
 }
+
+// BFS
+class Solution {
+    public int maxDepth(TreeNode root) {
+        if (root == null) return 0;
+        Queue<TreeNode> queue = new LinkedList<>();
+        queue.add(root);
+        int levels = 0;
+        while (!queue.isEmpty()) {
+            int size = queue.size();
+            for (int i = 0; i < size; i++) {
+                TreeNode current = queue.poll();
+                if (current.left != null) queue.add(current.left);
+                if (current.right != null) queue.add(current.right);
+            }
+            levels++;
+        }
+        return levels;
+    }
+}