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-# Algorithms 2019-2020 Python LEETCODE
-
-Check branches for information.
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+# Binary tree
+
++ [Binary Tree Level Order Traversal](#binary-tree-level-order-traversal)
+
+## Binary Tree Level Order Traversal
+
+https://leetcode.com/problems/binary-tree-level-order-traversal/
+
+```python
+# Definition for a binary tree node.
+# class TreeNode(object):
+#     def __init__(self, val=0, left=None, right=None):
+#         self.val = val
+#         self.left = left
+#         self.right = right
+class Solution(object):
+    def levelOrder(self, root):
+        res = []
+        self.dfs(root, 0, res)
+        return res
+
+    def dfs(self, root, level, res):
+        if not root:
+            return
+        if len(res) < level + 1:
+            res.append([])
+        res[level].append(root.val)
+        self.dfs(root.left, level + 1, res)
+        self.dfs(root.right, level + 1, res)
+
+```
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