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653. Two Sum IV – Input is a BST
Given a Binary Search Tree and a target number, return true if there exist two elements in the BST s…
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112. Path Sum
Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all…
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110. Balanced Binary Tree
Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary …
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270. Closest Binary Search Tree Value
Given a non-empty binary search tree and a target value, find the value in the BST that is closest t…
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100. Same Tree
Given two binary trees, write a function to check if they are equal or not. Two binary trees are con…
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107. Binary Tree Level Order Traversal II
Given a binary tree, return the bottom-up level order traversal of its nodes’ values. (ie, fro…
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257. Binary Tree Paths
Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 …