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]. 题目: 给一数组,n个元素,将数组向右移动循环移动k个元素. 思路: 注意题目的要求是循环移动,所以k可以是任意非负整数,但数组元素个数为n,因此k=k%n. 一种通用的思路就是: 1.翻转整个数组 :A[…

题目 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 this…

这是悦乐书的第184次更新,第186篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第43题(顺位题号是189).给定一个数组,将数组向右旋转k步,其中k为非负数.例如: 输入:[1,2,3,4,5,6,7],k = 3 输出:[5,6,7,1,2,3,4] 说明: 向右旋转1步:[7,1,2,3,4,5,6] 向右旋转2步:[6,7,1,2,3,4,5] 向右旋转3步:[5,6,7,1,2,3,4] 输入:[ - 1,-100,3,99],k = 2 输出:[3,9…

Given a set of distinct integers, S, return all possible subsets. Note: Elements in a subset must be in non-descending order. The solution set must not contain duplicate subsets. 题目要求 : 求整数数组的所有子集 注意: 1.子集元素按非降序排列 2.不包含重复的子集 解题思路: 求解这类诸如子集的题目,都可以采用回溯…

Given two words word1 and word2, find the minimum number of steps required to convert word1 to word2. (each operation is counted as 1 step.) You have the following 3 operations permitted on a word: a) Insert a characterb) Delete a characterc) Replace…

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]. 将数组的内容倒置,看例子就知道是什么意思: class Solution { public: void rotate(vector<int>& nums, int k) { if(k > n…

Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find the minimum element. You may assume no duplicate exists in the array. 题目: 给定一旋转有序数组,求该数组的最小值. 思路: 二分查找Binary Search 比较简单…

剑指offer 66. 构建乘积数组 题目: 给定一个数组A[0, 1, ..., n-1],请构建一个数组B[0, 1, ..., n-1],其中B中的元素B[i] = A[0] * A[1] * ... * A[i-1] * A[i +1] ... A[n-1].不能使用除法. 同leetcode 238 https://leetcode.com/problems/product-of-array-except-self/ 分析: 假如可以利用除法,则利用(A[0]*A[1]*...A[n-…

================================== LeetCode的一些算法题,都是自己做的,欢迎提出改进~~ LeetCode:http://oj.leetcode.com ================================== <Reverse Words in a String>-20140328 Given an input string, reverse the string word by word. For example, Given s =…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 题目: 给一无序数组,找到数组中从1开始第一个不出现的正整数. 要求O(n)的时间复杂度和常数空间复杂度…