You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Follow up: Could you do this in-place? 解题思路: 找规律即可,JAVA实现如下: static public void rotate(int[][] matrix) { int[][] matrixArray=new int[matrix.length][ma…

题目在这里 https://leetcode.com/problems/rotate-image/ [个人分析] 这个题目,我觉得就是考察基本功.考察细心的,算法方面没有太多东西,但是对于坐标的使用有较高要求. 放了两个版本的答案,第一个版本是自己写的,第二个是目前最佳答案的Java改写. [代码注释] Solution1: 思路比较直接.既然要求in-place,那就在修改之前,先保存原先在那个位置上的值,然后尾巴咬尾巴的去修改:大意可以参考下图 Solution2: 偏数学的方法,先把矩阵“…

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]. 解题思路: JAVA实现如下: public void rotate(int[] nums, int k) { k%=nums.length; k=nums.length-k; int[] nums2=ne…

Given a list, rotate the list to the right by k places, where k is non-negative. For example: Given 1->2->3->4->5->NULL and k = 2, return 4->5->1->2->3->NULL. 解题思路: 只需找到对应的位置,然后指向head,接着把之前节点指向null即可,注意k可以取大于length的值,所以k%=len…

题目要求:Rotate Image You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Follow up:Could you do this in-place? 代码如下: class Solution { public: void rotate(vector<vector<int> > &matrix) { const in…

Given a linked list, rotate the list to the right by k places, where k is non-negative. Example 1: Input: 1->2->3->4->5->NULL, k = 2 Output: 4->5->1->2->3->NULL Explanation: rotate 1 steps to the right: 5->1->2->3-&g…

Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Ensure that numbers within the set are sorted in ascending order. Example 1…

Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation. For example: Given "aacecaaa", return "aaacecaaa&qu…

Given a 2D board and a list of words from the dictionary, find all words in the board. Each word must be constructed from letters of sequentially adjacent cell, where "adjacent" cells are those horizontally or vertically neighboring. The same le…

Design a data structure that supports the following two operations: void addWord(word)bool search(word) search(word) can search a literal word or a regular expression string containing only letters a-z or .. A . means it can represent any one letter.…