摘要：
题目：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... 阅读全文
摘要：
题目：Given two binary trees, write a function to check if they are equal or not.Two binary trees are considered equal if they are structurally identical... 阅读全文
摘要：
题目：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 / ... 阅读全文