Well, since the head pointer may also be modified, we create a new_head that points to it to facilitate the reverse process. For the example list 1 -> 2 -> 3 -> 4 -> 5 in the problem statement, it will become 0 -> 1 -> 2 -> 3 -> 4…

LeetCode: Reverse Words in a String:Evaluate Reverse Polish Notation Evaluate the value of an arithmetic expression in Reverse Polish Notation. Valid operators are +, -, *, /. Each operand may be an integer or another expression. Some examples: ["2&q…

leetcode:Reverse Bits 本题目收获 移位(<<  >>), 或(|),与(&)计算的妙用 题目: Reverse bits of a given 32 bits unsigned integer.For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in bin…

LeetCode--Reverse String Question Write a function that takes a string as input and returns the string reversed. Example: Given s = "hello", return "olleh". Answer class Solution { public: string reverseString(string s) { string str(s.…

Write a function that takes a string as input and reverse only the vowels of a string. Example 1:Given s = "hello", return "holle". Example 2:Given s = "leetcode", return "leotcede". 这道题让我们翻转字符串中的元音字母,元音字母有五个a,e,i,o…

Write a function that takes a string as input and returns the string reversed. Example: Given s = "hello", return "olleh". 这道题没什么难度,直接从两头往中间走,同时交换两边的字符即可,参见代码如下: 解法一: class Solution { public: string reverseString(string s) { , right =…

Reverse a singly linked list. click to show more hints. Hint: A linked list can be reversed either iteratively or recursively. Could you implement both? 之前做到Reverse Linked List II 倒置链表之二的时候我还纳闷怎么只有二没有一呢,原来真是忘了啊,现在才加上,这道题跟之前那道比起来简单不少,题目为了增加些许难度,让我们分别用…

Reverse bits of a given 32 bits unsigned integer. For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as00111001011110000010100101000000). Follow up:If this function i…

Given an input string, reverse the string word by word. A word is defined as a sequence of non-space characters.The input string does not contain leading or trailing spaces and the words are always separated by a single space.For example,Given s = "t…

Given an input string, reverse the string word by word. For example, Given s = "the sky is blue", return "blue is sky the". Update (2015-02-12): For C programmers: Try to solve it in-place in O(1) space. click to show clarification. Cl…

Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2->5->NULL. Note:Given m, n satisfy the following condition:1 ≤ m ≤ n ≤ lengt…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. If the number of nodes is not a multiple of k then left-out nodes in the end should remain as it is. You may not alter the values in the nodes, only nod…

Reverse digits of an integer. Example1: x = 123, return 321 Example2: x = -123, return -321 click to show spoilers. Have you thought about this? Here are some good questions to ask before coding. Bonus points for you if you have already thought throu…

原题链接在这里:https://leetcode.com/problems/reverse-vowels-of-a-string/ 题目: Write a function that takes a string as input and reverse only the vowels of a string. Example 1:Given s = "hello", return "holle". Example 2:Given s = "leetcod…

原题链接在这里:https://leetcode.com/problems/reverse-string/ 题目: Write a function that takes a string as input and returns the string reversed. Example:Given s = "hello", return "olleh". 题解: Reverse string是常见题, string在Java中是primitive类型, 一旦生成不…

原题链接在这里:https://leetcode.com/problems/reverse-words-in-a-string-ii/ 题目: Given an input string, reverse the string word by word. A word is defined as a sequence of non-space characters. The input string does not contain leading or trailing spaces and…

Title: Given an input string, reverse the string word by word. For example,Given s = "the sky is blue",return "blue is sky the". https://leetcode.com/problems/reverse-words-in-a-string/ 思路:先将字符串全部逆转,在将每个单词逆转.具体实现,要注意空格,所以对字符串倒过来处理. cla…

Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order. Example 1: Input: "Let's take LeetCode contest" Output: "s'teL ekat edoCteeL tsetnoc"…

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…

my solution: class Solution { public: int reversePairs(vector<int>& nums) { int length=nums.size(); ; ;i<length;i++) { ;j<length;j++) { if(nums[i]>2*nums[j]) count++; } } return count; } }; wrong answer : because   2147483647*2 is -2 (i…

第一天上课,数据库老师说对于计算机系的学生,凡是在课本上学到的专业知识都是过时的.深以为然,感觉大学两年半真的不知道学了什么,为未来感到担忧,C++也不敢说是精通,入门还差不多.最近丧的不行,不管怎么样,每天还是要进步一点点. 题目: Given a 32-bit signed integer, reverse digits of an integer. Example 1: Input: 123 Output: 321 感觉不难,写了才发现自己没考虑溢出的问题,为判断溢出折腾了好久,心好累,提…

原题地址:https://oj.leetcode.com/problems/reverse-linked-list-ii/ 题意: Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2->5->NULL.…

原题地址:https://oj.leetcode.com/problems/reverse-words-in-a-string/ 题意: Given an input string, reverse the string word by word. For example,Given s = "the sky is blue",return "blue is sky the". 解题思路:这题很能体现python处理字符串的强大功能. 代码: class Solut…

Reverse digits of an integer. Example1: x = 123, return 321Example2: x = -123, return -321 click to show spoilers. Have you thought about this? Here are some good questions to ask before coding. Bonus points for you if you have already thought throug…

原题链接在这里:https://leetcode.com/problems/reverse-words-in-a-string-iii/#/description 题目: Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order. Example 1: Inpu…

原题链接在这里:https://leetcode.com/problems/reverse-string-ii/#/description 题目: 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 l…

一.题目: Given an input string, reverse the string word by word. For example, Given s = "the sky is blue", return "blue is sky the". click to show clarification. Clarification: What constitutes a word? A sequence of non-space characters c…

Reverse a linked list from position m to n. Do it in-place and in one-pass. For example:Given 1->2->3->4->5->NULL, m = 2 and n = 4, return 1->4->3->2->5->NULL. Note:Given m, n satisfy the following condition:1 ≤ m ≤ n ≤ lengt…

Reverse a singly linked list. 这题因为palindrome linked list 的时候需要就顺便做了一下.利用三个指针:prev, now, next 相互倒腾就行. /** * Definition for singly-linked list. * function ListNode(val) { * this.val = val; * this.next = null; * } */ /** * @param {ListNode} head * @retu…

Given a linked list, reverse the nodes of a linked list k at a time and return its modified list. If the number of nodes is not a multiple of k then left-out nodes in the end should remain as it is. You may not alter the values in the nodes, only nod…