leetcode 199. Binary Tree Right Side View 这个题实际上就是把每一行最右侧的树打印出来,所以实际上还是一个层次遍历. 依旧利用之前层次遍历的代码,每次大的循环存储的是一行的节点,最后一个节点就是想要的那个节点 class Solution { public: vector<int> rightSideView(TreeNode* root) { vector<int> result; if(root == NULL) return resul…

You are given a perfect binary tree where all leaves are on the same level, and every parent has two children. The binary tree has the following definition: struct Node { int val; Node *left; Node *right; Node *next; } Populate each next pointer to p…

https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/ Follow up for problem "Populating Next Right Pointers in Each Node". What if the given tree could be any binary tree? Would your previous solution still work? Note: Yo…

问题 给出如下结构的二叉树: struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; } 填充每一个next指针使其指向自己的右边邻居节点.如果没有右边的邻居节点,next指针须设成NULL. 在开始时,所有的next指针被初始化成NULL. 注意: 你只能使用常数级别的额外空间 你可以假设该树为完全二叉树(即所有叶子节点都在同一层,而且每个父节点都有两个子节点). 例如,给出如下完全二…

Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; } Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL. Initially, al…

116. 填充每个节点的下一个右侧节点指针 给定一个完美二叉树,其所有叶子节点都在同一层,每个父节点都有两个子节点.二叉树定义如下: struct Node { int val; Node *left; Node *right; Node *next; } 填充它的每个 next 指针,让这个指针指向其下一个右侧节点.如果找不到下一个右侧节点,则将 next 指针设置为 NULL. 初始状态下,所有 next 指针都被设置为 NULL. 示例: 输入:{"$id":"1&qu…

116. 填充同一层的兄弟节点 其实就是个二叉树的层次遍历 class Solution { public void connect(TreeLinkNode root) { if (root == null) return; LinkedList<TreeLinkNode> queue = new LinkedList<>(); queue.offer(root); TreeLinkNode flag = root; TreeLinkNode last = null; while…

Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; } Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL. Initially, al…

Problem: Given two integers representing the numerator and denominator of a fraction, return the fraction in string format. If the fractional part is repeating, enclose the repeating part in parentheses. For example, Given numerator = 1, denominator…

Given a binary tree struct TreeLinkNode { TreeLinkNode *left; TreeLinkNode *right; TreeLinkNode *next; }  Populate each next pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL. Initially, a…