Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. ExampleGiven the list [[1,1],2,[1,1]], By calling next repeatedly until hasNext…

Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1: Given the list [[1,1],2,[1,1]], By calling next repeatedly until hasN…

Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1:Given the list [[1,1],2,[1,1]], By calling next repeatedly until hasNe…

Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1:Given the list [[1,1],2,[1,1]], By calling next repeatedly until hasNe…

Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1: Input: [[1,1],2,[1,1]] Output: [1,1,2,1,1] Explanation: By calling ne…

Given a nested list of integers, return the sum of all integers in the list weighted by their depth. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1: Given the list [[1,1],2,[1,1]], return…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 递归+队列 栈 日期 题目地址:https://leetcode.com/problems/flatten-nested-list-iterator/description/ 题目描述 Given a nested list of integers, implement an iterator to flatten it. Each element i…

Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1: Given the list [[1,1],2,[1,1]], By calling next repeatedly until hasN…

Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Notice You don't need to implement the remove method. Example Given the list [[1…

Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1:Given the list [[1,1],2,[1,1]], By calling next repeatedly until hasNe…

［抄题］: Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1:Given the list [[1,1],2,[1,1]], By calling next repeatedly until…

题目如下: Given a nested list of integers, implement an iterator to flatten it. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1: Input: [[1,1],2,[1,1]] Output: [1,1,2,1,1] Explanation: By call…

List里可以有int或者List,然后里面的List里面可以再有List. 用Stack来做比较直观 Iterator无非是next()或者hasNext()这2个方程 一开始我想的是hasNext()就简单的返还是不是空就行,主要的操作在next()里,结果发现无线循环..好蠢 然后看网上答案改的在hasNext()里准备好,其实一开始的想法不一定错,二刷可以试试. 简单的说就是先都塞到STACK里面,如果Peek的元素是单一int就返还TRUE,然后next()会直接返还那个int. 如果…

https://leetcode.com/problems/flatten-nested-list-iterator/…

341. 扁平化嵌套列表迭代器 给你一个嵌套的整型列表.请你设计一个迭代器,使其能够遍历这个整型列表中的所有整数. 列表中的每一项或者为一个整数,或者是另一个列表.其中列表的元素也可能是整数或是其他列表. 示例 1: 输入: [[1,1],2,[1,1]] 输出: [1,1,2,1,1] 解释: 通过重复调用 next 直到 hasNext 返回 false,next 返回的元素的顺序应该是: [1,1,2,1,1]. 示例 2: 输入: [1,[4,[6]]] 输出: [1,4,6] 解释:…

[python]Leetcode每日一题-扁平化嵌套列表迭代器 [题目描述] 给你一个嵌套的整型列表.请你设计一个迭代器,使其能够遍历这个整型列表中的所有整数. 列表中的每一项或者为一个整数,或者是另一个列表.其中列表的元素也可能是整数或是其他列表. 示例1: 输入: [[1,1],2,[1,1]] 输出: [1,1,2,1,1] 解释: 通过重复调用 next 直到 hasNext 返回 false,next 返回的元素的顺序应该是: [1,1,2,1,1]. 示例2: 输入: [1,[4,[…

Given a nested list of integers, return the sum of all integers in the list weighted by their depth. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1:Given the list [[1,1],2,[1,1]], return …

Given a nested list of integers, return the sum of all integers in the list weighted by their depth. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Different from the previous question where weight…

Flatten a binary tree to a fake "linked list" in pre-order traversal. Here we use the right pointer in TreeNode as the next pointer in ListNode. Notice Don't forget to mark the left child of each node to null. Or you will get Time Limit Exceeded…

Given a nested list of integers, return the sum of all integers in the list weighted by their depth. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Different from the previous question where weight…

list 是 Python 中使用最频繁的数据类型, 标准库里面有丰富的函数可以使用.不过,如果把多维列表转换成一维列表(不知道这种需求多不多),还真不容易找到好用的函数,要知道Ruby.Mathematica.Groovy中可是有flatten的啊.如果列表是维度少的.规则的,还算好办例如: li=[[1,2],[3,4],[5,6]] print [j for i in li for j in i] #or from itertools import chain print list(cha…

Given a nested list of integers, return the sum of all integers in the list weighted by their depth. Each element is either an integer, or a list -- whose elements may also be integers or other lists. Example 1: Input: [[1,1],2,[1,1]] Output: 10 Expl…

描述 给定一个链表,判断它是否有环. 样例 给出 -21->10->4->5, tail connects to node index 1,返回 true. 这里解释下,题目的意思,在英文原题中,tail connects to node index 1 表示的是节点 5 还要链接回索引号 为 1 的节点. 一个典型的带环链表如下: 挑战 不要使用额外的空间 代码 GitHub 的源代码,请访问下面的链接: https://github.com/cwiki-us/java-tutoria…

Sometimes, we run into situations where we end up with a Maybe within the context of another Maybe. Nested structures like this can get really confusing to work with. In this lesson, we’ll look at an example of this and see how chaincan help us out b…

题目: 在O(1)时间复杂度删除链表节点 给定一个单链表中的表头和一个等待被删除的节点(非表头或表尾).请在在O(1)时间复杂度删除该链表节点.并在删除该节点后,返回表头. 样例 给定 1->2->3->4,和节点 3,返回 1->2->4. 解题: 方法好贱,先把要删除节点后面一个节点的值赋给删除节点,这样需要删除节点就删除了,再把删除节点指向删除节点后面节点的节点 就像这样: node.val = node.next.val; node.next = node.next.…

C++ Traverse /** * Definition of TreeNode: * class TreeNode { * public: * int val; * TreeNode *left, *right; * TreeNode(int val) { * this->val = val; * this->left = this->right = NULL; * } * } */ class Solution { public: /** * @param root: a Tree…

题目描述: 分析:因为题目要求不能用循环,而且只给了要删除的节点,并没有给链表.所以我无法取得要删除节点的前一个节点,只能在待删除的节点以及下一个节点上做文章.我的思路是:将待删除的节点的下一个节点的值赋给待删除节点,然后让待删除的节点的next指向待删除节点的next的next. 我的代码: /** * Definition for ListNode. * public class ListNode { * int val; * ListNode next; * ListNode(int va…

Remove all elements from a linked list of integers that have value val. Have you met this question in a real interview?     Example Given 1->2->3->3->4->5->3, val = 3, you should return the list as 1->2->4->5 LeetCode上的原题,请参见我之前…

题目 将一个二叉查找树按照中序遍历转换成双向链表 给定一个二叉查找树: 4 / \ 2 5 / \ 1 3 返回 1<->2<->3<->4<->5. 解题 /** * Definition of TreeNode: * public class TreeNode { * public int val; * public TreeNode left, right; * public TreeNode(int val) { * this.val = val;…

Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST. Calling next() will return the next smallest number in the BST. Note: next() and hasNext() should run in average O(1) time and uses…