摘要: Given a binary tree, return the bottom-up level order traversal of its nodes' values. (ie, from left to right, level by level from leaf to root). For 阅读全文
posted @ 2016-05-04 19:24 Black_Knight 阅读(186) 评论(0) 推荐(0) 编辑
摘要: Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; } Populate each next pointer to point to its ne 阅读全文
posted @ 2016-05-04 17:52 Black_Knight 阅读(169) 评论(0) 推荐(0) 编辑
摘要: Given an array where elements are sorted in ascending order, convert it to a height balanced BST. 把一个有序的数组转换为一颗平衡二叉搜索树。每次找到中间节点作为根节点,根节点左边部分转换为左子树,右边部 阅读全文
posted @ 2016-05-04 17:18 Black_Knight 阅读(171) 评论(0) 推荐(0) 编辑
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. 通过树的中序序列和前序序列 阅读全文
posted @ 2016-05-04 15:39 Black_Knight 阅读(295) 评论(0) 推荐(0) 编辑
摘要: Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only 阅读全文
posted @ 2016-05-04 11:17 Black_Knight 阅读(219) 评论(0) 推荐(0) 编辑
摘要: Given n, generate all structurally unique BST's (binary search trees) that store values 1...n. For example,Given n = 3, your program should return all 阅读全文
posted @ 2016-05-03 20:10 Black_Knight 阅读(202) 评论(0) 推荐(0) 编辑
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 tree and sum 阅读全文
posted @ 2016-05-03 16:07 Black_Knight 阅读(214) 评论(0) 推荐(0) 编辑
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 unique BST' 阅读全文
posted @ 2016-05-03 10:28 Black_Knight 阅读(176) 评论(0) 推荐(0) 编辑
摘要: Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary tree is symmetric: 1 / \ 2 2 / 阅读全文
posted @ 2016-05-03 09:46 Black_Knight 阅读(157) 评论(0) 推荐(0) 编辑
摘要: Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. F 阅读全文
posted @ 2016-04-28 10:32 Black_Knight 阅读(177) 评论(0) 推荐(0) 编辑