摘要：
Given inorder and postorder traversal of a tree, construct the binary tree.Note: You may assume that duplicates do not exist in the tree.clas... 阅读全文
摘要：
Given preorder and inorder traversal of a tree, construct the binary tree.Note: You may assume that duplicates do not exist in the tree.class... 阅读全文
摘要：
Given n, how many structurally unique BST’s (binary search trees) that store values 1…n?For example, Given n = 3, there are a total of 5 uniq... 阅读全文
摘要：
解决二叉树的很多问题的方案都是基于对二叉树的遍历。遍历二叉树的前序，中序，后序三大方法算是计算机科班学生必写代码了。其递归遍历是人人都能信手拈来，可是在手生时写出非递归遍历恐非易事。正因为并非易事，所以网上出现无数的介绍二叉树非递归遍历方法的文章。可是大家需要的真是那些非递归遍历代... 阅读全文
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Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree.According to the definition of LCA on Wikipedia: “T... 阅读全文
摘要：
Given a binary tree and a sum, find all root-to-leaf paths where each path’s sum equals the given sum.For example: Given the below binary tre... 阅读全文