匡子语

摘要： Given two integersnandk, return all possible combinations ofknumbers out of 1 ...n.For example,Ifn= 4 andk= 2, a solution is:[ [2,4], [3,4], [2,3],... 阅读全文

摘要： Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.思路：题目看上去好像很难，但实际上很简单，递归做就行，每次找到左右子树对应的子链表... 阅读全文

摘要： Given a sorted linked list, delete all duplicates such that each element appear onlyonce.For example,Given1->1->2, return1->2.Given1->1->2->3->3, retu... 阅读全文

摘要： Sort a linked list using insertion sort.思路：用插入排序对链表排序。插入排序是指每次在一个排好序的链表中插入一个新的值。注意：把排好序的部分和未排序的部分完全分开，指针不要有交叉。 即不会通过->next 重叠class Solution {public: ... 阅读全文

摘要： Given a linked list, remove thenthnode from the end of list and return its head.For example, Given linked list: 1->2->3->4->5, and n = 2. After re... 阅读全文

摘要： You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single ... 阅读全文

摘要： Given a binary tree, return thezigzag level ordertraversal of its nodes' values. (ie, from left to right, then right to left for the next level and al... 阅读全文

摘要： A peak element is an element that is greater than its neighbors.Given an input array wherenum[i] ≠ num[i+1], find a peak element and return its index.... 阅读全文

摘要： Given a list of non negative integers, arrange them such that they form the largest number.For example, given[3, 30, 34, 5, 9], the largest formed num... 阅读全文

摘要： Given a string containing just the characters'(',')','{','}','['and']', determine if the input string is valid.The brackets must close in the correct ... 阅读全文