大意: 给定字符串$a$,$b$, $b$可以任选一段连续的区间删除, 要求最后$b$是$a$的子序列, 求最少删除区间长度. 删除一段连续区间, 那么剩余的一定是一段前缀和后缀. 判断是否是子序列可以用序列自动机, 最后双指针合并前缀与后缀的答案. #include <iostream> #include <sstream> #include <algorithm> #include <cstdio> #include <math.h> #in…

大意: 给定字符串$s$, $p$, 对于$0\le x\le |s|$, 求$s$删除$x$个字符后, $p$在$s$中的最大出现次数. 显然答案是先递增后递减的, 那么问题就转化求最大出现次数为$y$时, 求$S$所需要删除的最少字符数. 先暴力O(n^2)求出以每个字符开头匹配完一个$p$后的最小右端点, 然后$dp$即可. #include <iostream> #include <sstream> #include <algorithm> #include &…

golang用strings.Split切割字符串 kv := strings.Split(authString, " ") if len(kv) != 2 || kv[0] != "Bearer" { beego.Debug("AuthString invalid:"+authString) base.ReturnError(errors.New("AuthString invalid:"+authString)) retu…

Given two words word1 and word2, find the minimum number of steps required to make word1 and word2 the same, where in each step you can delete one character in either string. Example 1: Input: "sea", "eat" Output: 2 Explanation: You ne…

Given two strings s1, s2, find the lowest ASCII sum of deleted characters to make two strings equal. Example 1: Input: s1 = "sea", s2 = "eat" Output: 231 Explanation: Deleting "s" from "sea" adds the ASCII value of…

Cpdeforces 762C 题目大意: 给定两个字符串a,b\((len \leq 10^5)\),让你去b中的一个连续的字段,使剩余的b串中的拼接起来的两个串是a穿的子序列.最大化这个字串的长度. 题解: 删除这个操作不太好说,我们先换一个思路:实际上删除就是在b串中分别取出两个不相交的前缀和后缀,使得这两个串在a串中不重叠地出现 我们发现答案具有显然的单调性,所以我们首先二分答案(二分删去的字串长度). 现在来考虑如何进行判定: 一个很直接的思路就是枚举所有的符合条件的前缀和后缀 然后对…

Design an algorithm to encode a list of strings to a string. The encoded string is then sent over the network and is decoded back to the original list of strings. Machine 1 (sender) has the function: string encode(vector<string> strs) { // ... your…

Given two strings s1, s2, find the lowest ASCII sum of deleted characters to make two strings equal. Example 1: Input: s1 = "sea", s2 = "eat" Output: 231 Explanation: Deleting "s" from "sea" adds the ASCII value of…

Given two words word1 and word2, find the minimum number of steps required to make word1 and word2 the same, where in each step you can delete one character in either string. Example 1: Input: "sea", "eat" Output: 2 Explanation: You ne…

Given a list of strings, you could concatenate these strings together into a loop, where for each string you could choose to reverse it or not. Among all the possible loops, you need to find the lexicographically biggest string after cutting the loop…