moluchase的专栏

Given an array of integers, find two numbers such that they add up to a specific target number.The function twoSum should return indices of the two numbers such that they add up to the target, whe

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.Subscribe to see which companies asked this questio

Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.The brackets must close in the correct order, "()" and "()[]{}" are all va

Given a linked list, remove the nth node from the end of list and return its head.For example, Given linked list: 1->2->3->4->5, and n = 2. After removing the second node from the end, the

Given a digit string, return all possible letter combinations that the number could represent.A mapping of digit to letters (just like on the telephone buttons) is given below.Input:Digit st

Given an integer, convert it to a roman numeral.Input is guaranteed to be within the range from 1 to 3999.先是了解罗马数的构成基本字符IVXLCD

Given n non-negative integers a1, a2, ..., an, where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpoints of line i is at (i, ai) and (i, 0). Fin

'.' Matches any single character.'*' Matches zero or more of the preceding element.The matching should cover the entire input string (not partial).The function prototype should be:bool isMatch(c

Determine whether an integer is a palindrome. Do this without extra space.题目要求不要开辟额外的空间回文数：逆序数和正序数不变，对于越界，如果逆序后越界说明不是回文数如果没有这个要求我立马会用字符串解决，不过这样的要求倒是学到一种新方法，将数字逆过来进行比较，对于越界的问题，将最高位和最低位比较，不相等就返回fa

Implement atoi to convert a string to an integer.Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input ca

Reverse digits of an integer.Example1: x = 123, return 321Example2: x = -123, return -321Here are some good questions to ask before coding. Bonus points for you if you have already thoug

P A H NA P L S I I GY I RAnd then read line by line: "PAHNAPLSIIGYIR"Write the code that will take a string and make this conversion given a number of rows:string convert(stri

Given a string S, find the longest palindromic substring in S. You may assume that the maximum length of S is 1000, and there exists one unique longest palindromic substring.开始竟然看成最大的逆序子串了回文

There are two sorted arrays nums1 and nums2 of size m and n respectively. Find the median of the two sorted arrays. The overall run time complexity should be O(log (m+n)).double findMedianSortedAr

Given a string, find the length of the longest substring without repeating characters. For example, the longest substring without repeating letters for "abcabcbb" is "abc", which the length is 3. Fo

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 digit. Add the two numbers and return it as a li

Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.For example, given n = 3, a solution set is:[ "((()))", "(()())", "(())()", "()(())