Problem description for balanced-binary-tree

leetcode/balanced-binary-tree/Readme.md

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+Given a binary tree, determine if it is height-balanced.
+
+ 
+Example 1:
+
+
+Input: root = [3,9,20,null,null,15,7]
+Output: true
+
+
+Example 2:
+
+
+Input: root = [1,2,2,3,3,null,null,4,4]
+Output: false
+
+
+Example 3:
+
+
+Input: root = []
+Output: true
+
+
+ 
+Constraints:
+
+
+	The number of nodes in the tree is in the range [0, 5000].
+	-104 <= Node.val <= 104
+