Given an array A of positive integers, call a (contiguous, not necessarily distinct) subarray of A good if the number of different integers in that subarray is exactly K. (For example, [1,2,3,1,2] has 3 different integers: 1, 2, and 3.) Return the nu…

题目链接:https://leetcode.com/problems/subarrays-with-k-different-integers/ 题意:已知一个全为正数的数组A,1<=A.length<=20000,1<=A[i]<=A.length,1<=K<=A.length,问A中恰好有K个不同的元素的子数组个数有多少个 思路:对于考虑到数据范围较大,暴力显然不可取.对于每个位置i,如果用min_k[i] 表示起始位置为i的子数组存在k个元素的最小结束位置,用min…

Given an array A of positive integers, call a (contiguous, not necessarily distinct) subarray of A good if the number of different integers in that subarray is exactly K. (For example, [1,2,3,1,2] has 3different integers: 1, 2, and 3.) Return the num…

Given a non-empty string s and an integer k, rearrange the string such that the same characters are at least distance k from each other. All input strings are given in lowercase letters. If it is not possible to rearrange the string, return an empty…

滑动窗口基础 滑动窗口常用来解决求字符串子串问题,借助map和计数器,其能在O(n)时间复杂度求子串问题.滑动窗口和双指针(Two pointers)有些类似,可以理解为往同一个方向走的双指针.常用滑动窗口代码框架如下: //3. Longest Substring Without Repeating Characters int lengthOfLongestSubstring(string s) { vector<,); //用于对窗口内的各个字符计数 ,end=,res=; //窗口计数器…

滑动窗口基础 滑动窗口常用来解决求字符串子串问题,借助map和计数器,其能在O(n)时间复杂度求子串问题.滑动窗口和双指针(Two pointers)有些类似,可以理解为往同一个方向走的双指针.常用滑动窗口代码框架如下: //3. Longest Substring Without Repeating Characters int lengthOfLongestSubstring(string s) { vector<,); //用于对窗口内的各个字符计数 ,end=,res=; //窗口计数器…

# Title Solution Acceptance Difficulty Frequency     4 Median of Two Sorted Arrays       27.2% Hard     10 Regular Expression Matching       25.6% Hard     23 Merge k Sorted Lists       35.8% Hard     25 Reverse Nodes in k-Group       37.7% Hard    …

992. Subarrays with K Different Integers 给定一个正整数数组,计算刚好有K个不同数的子数组的个数.(For example, [1,2,3,1,2] has 3 different integers: 1, 2, and 3.) 解法一:slide window 如果是求最多有K个不同元素的子数组,那么就是典型的slide window的题目,只需要在这个典型题目上增添一步: exactly(K) = atMost(K) - atMost(K-1) cla…

请点击页面左上角 -> Fork me on Github 或直接访问本项目Github地址:LeetCode Solution by Swift    说明:题目中含有$符号则为付费题目. 如:[Swift]LeetCode156.二叉树的上下颠倒 $ Binary Tree Upside Down 请下拉滚动条查看最新 Weekly Contest!!! Swift LeetCode 目录 | Catalog 序        号 题名Title 难度     Difficulty  两数之…

Given a string S, find the length of the longest substring T that contains at most two distinct characters.For example,Given S = “eceba”,T is “ece” which its length is 3. 这道题给我们一个字符串,让我们求最多有两个不同字符的最长子串.那么我们首先想到的是用哈希表来做,哈希表记录每个字符的出现次数,然后如果哈希表中的映射数量超过两…