BaibuT的专栏

8. String to Integer (atoi) 题目的原意是 实现atoi 的方法来将String转换成数值。 方法的基本要求： 先去除第一个字母前的空格，然后判断第一个字母看是否是+，-，数字。如果是+给个+符号并且将光标移到下一个字母，如果是-， 给个-符号并且将光标移到下一个字母。 如果是数字，需要将数字的Strng格式的部分转换成数值。 例子： Input: "42"  O...

3. Longest Substring Without Repeating Characters given: a string, find the length of the longest substring without repeating characters.         e.g. the longest substring without repeating letters

1. Valid Anagram given: two strings s and t, write a function to determine if t is an anagram of s. e.g. s="anagram", t="nagaram", return true. s="rat", t="car", return false. strategy: u

238. Product of Array Except Self given: an array of n integers where n>1, nums, return an array output such that output[i] is equal to the product of all the  elements of nums except nums[i].

11. Container With Most Water 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 li

125. Valid Palindrome given: a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. e.g.  "A man, a plan, a canal: Panama" is a palindrome. "race a

189. Rotate Array requirement: rotate an array of n elements to the right by k steps. for example, with n=7 and k=3, the array [1,2,3,4,5,6,7] is rotated to [5,6,7,1,2,3,4] note: try to come up

186. Reverse Words in a String II 题目的原意是用就地操作来实现函数对给定的char string 进行逐个单词的反转。 存在的挑战： 1. 在不使用split的方法的情况下实现。 2. 旋转array从左到右就地操作，而且不申请额外的空间。   解题思路1：  1. 先反转整个string。 2. 再反转单个词。 3. 这样需要写一个swap方法来置换...

167. Two Sum II - Input array is sorted Given: an array of integers that is already sorted in ascending order, find two  numbers such that  they add up to a specific target number. output: the

Given: a sorted array,  to do: remove the duplicates in place such that each element appear only once  and return the new length requirment: do not allocate extra space for another array, you m

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

161. One Edit Distance 题目的原意: 写一个函数判断两个给定的String是否是编辑距离为一。 给定条件：两个字符串。 解题思路：用one edit的算法会超时，可以利用只有一个编辑的距离的特点。将问题细分为出现一个距离的一下几种情况。               1. 两个字符串长度一样的时候，说明只有一个字符串不一样，所以只需要看对应位置的连个字符是否一致，是否只...