一天一道LeetCode系列 (一)题目 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 cases. Notes: It is intended for t…
题目: 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 cases. Notes: It is intended for this problem to be…
题目描述: 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 cases. Notes: It is intended for this problem to…
我现在在做一个叫<leetbook>的免费开源书项目,力求提供最易懂的中文思路,目前把解题思路都同步更新到gitbook上了,需要的同学可以去看看 书的地址:https://hk029.gitbooks.io/leetbook/ 008. String to Integer (atoi) [E] 题目 Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cas…
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 cases. Notes: It is intended for this problem to be spe…
Implement atoi which converts a string to an integer. The function first discards as many whitespace characters as necessary until the first non-whitespace character is found. Then, starting from this character, takes an optional initial plus or minu…
原题地址: 344 Reverse String: https://leetcode.com/problems/reverse-string/description/ 541 Reverse String II: https://leetcode.com/problems/reverse-string-ii/description/ 题目&&解法: 1.Reverse String: Write a function that takes a string as input and ret…
You need to construct a string consists of parenthesis and integers from a binary tree with the preorder traversing way. The null node needs to be represented by empty parenthesis pair "()". And you need to omit all the empty parenthesis pairs t…
Special binary strings are binary strings with the following two properties: The number of 0's is equal to the number of 1's. Every prefix of the binary string has at least as many 1's as 0's. Given a special string S, a move consists of choosing two…
Given a string containing only three types of characters: '(', ')' and '*', write a function to check whether this string is valid. We define the validity of a string by these rules: Any left parenthesis '(' must have a corresponding right parenthesi…
Design and implement a data structure for a compressed string iterator. It should support the following operations: next and hasNext. The given compressed string will be in the form of each letter followed by a positive integer representing the numbe…
Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutations is the substring of the second string. Example 1: Input:s1 = "ab" s2 = "eidbaooo"…
S and T are strings composed of lowercase letters. In S, no letter occurs more than once. S was sorted in some custom order previously. We want to permute the characters of T so that they match the order that S was sorted. More specifically, if x occ…
Given an encoded string, return it's decoded string. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note that k is guaranteed to be a positive integer. You may assume th…
https://leetcode.com/problems/binary-string-with-substrings-representing-1-to-n/ Given a binary string S (a string consisting only of '0' and '1's) and a positive integer N, return true if and only if for every integer X from 1 to N, the binary repre…
https://leetcode.com/problems/di-string-match/ Given a string S that only contains "I" (increase) or "D" (decrease), let N = S.length. Return any permutation A of [0, 1, ..., N] such that for all i = 0, ..., N-1: If S[i] == "I&quo…
原题链接在这里:https://leetcode.com/problems/permutation-in-string/description/ 题目: Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutations is the substring of…
原题链接在这里:https://leetcode.com/problems/valid-parenthesis-string/description/ 题目: Given a string containing only three types of characters: '(', ')' and '*', write a function to check whether this string is valid. We define the validity of a string by…
原题链接在这里:https://leetcode.com/problems/design-compressed-string-iterator/description/ 题目: Design and implement a data structure for a compressed string iterator. It should support the following operations: next and hasNext. The given compressed string…
Given a string and an integer k, you need to reverse the first k characters for every 2k characters counting from the start of the string. If there are less than k characters left, reverse all of them. If there are less than 2k but greater than or eq…
A string of '0's and '1's is monotone increasing if it consists of some number of '0's (possibly 0), followed by some number of '1's (also possibly 0.) We are given a string S of '0's and '1's, and we may flip any '0' to a '1' or a '1' to a '0'. Retu…
Two strings X and Y are similar if we can swap two letters (in different positions) of X, so that it equals Y. For example, "tars" and "rats" are similar (swapping at positions 0 and 2), and "rats" and "arts" are si…
An encoded string S is given. To find and write the decoded string to a tape, the encoded string is read one character at a time and the following steps are taken: If the character read is a letter, that letter is written onto the tape. If the chara…
Given a string S, check if the letters can be rearranged so that two characters that are adjacent to each other are not the same. If possible, output any possible result. If not possible, return the empty string. Example 1: Input: S = "aab" Out…