add: Maximum depth of binary tree

Author: Yongseok-Choi-dev

maximum-depth-of-binary-tree/YoungSeok-Choi.java

@@ -0,0 +1,35 @@
+import java.util.LinkedList;
+import java.util.Queue;
+
+// 시간복잡도 O(n)
+class Solution {
+    public int depth = 0;
+    public int maxDepth(TreeNode root) {
+
+        if(root == null) {
+            return depth;
+        }
+        
+        Queue<TreeNode> q = new LinkedList<>();
+        q.add(root);
+
+        while(!q.isEmpty()) {
+            int size = q.size();
+            depth++;
+
+            for(int i = 0; i < size; i++) {
+                TreeNode p = q.poll();
+
+                if(p.right != null) {
+                    q.add(p.right);
+                }
+
+                if(p.left != null) {
+                    q.add(p.left);
+                }
+            }
+        }
+
+        return depth;
+    }
+}