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“…

题目参见这里 https://leetcode.com/problems/longest-consecutive-sequence/ 这个题目我感觉很难,看了半天别人写的答案,才明白个所以然.下面的代码是我自己的改编,写的好像很复杂的样子,主要也是为了方便自己理解,耐着性子看完,应该就理解了. [个人分析]: 题目难度主要是要求O(N)完成.本来最自然的想法是先排序然后再去扫一遍得到结果,可是这样,明显就是O(NlgN).怎么样从NlgN 提高到O(N)呢?  ==> 空间换时间,空间从O(1)…

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…

leetcode - 48. Rotate Image - Medium descrition You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note: You have to rotate the image in-place, which means you have to modify the input 2D matrix direct…

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…

题目描述: 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 as many solutions as you can, there are at least 3 different ways to solve th…

题目: You are given an n x n 2D matrix representing an image. Rotate the image by 90 degrees (clockwise). Note:You have to rotate the image in-place, which means you have to modify the input 2D matrix directly. DO NOT allocate another 2D matrix and do…