Codeforces 156 A——Message——————【思维题】
2 seconds
256 megabytes
standard input
standard output
Dr. Moriarty is about to send a message to Sherlock Holmes. He has a string s.
String p is called a substring of string s if you can read it starting from some position in the string s. For example, string "aba" has six substrings: "a", "b", "a", "ab", "ba", "aba".
Dr. Moriarty plans to take string s and cut out some substring from it, let's call it t. Then he needs to change the substring t zero or more times. As a result, he should obtain a fixed string u (which is the string that should be sent to Sherlock Holmes). One change is defined as making one of the following actions:
- Insert one letter to any end of the string.
- Delete one letter from any end of the string.
- Change one letter into any other one.
Moriarty is very smart and after he chooses some substring t, he always makes the minimal number of changes to obtain u.
Help Moriarty choose the best substring t from all substrings of the string s. The substring t should minimize the number of changes Moriarty should make to obtain the string u from it.
The first line contains a non-empty string s, consisting of lowercase Latin letters. The second line contains a non-empty string u, consisting of lowercase Latin letters. The lengths of both strings are in the range from 1 to 2000, inclusive.
Print the only integer — the minimum number of changes that Dr. Moriarty has to make with the string that you choose.
aaaaa
aaa
0
abcabc
bcd
1
abcdef
klmnopq
7
In the first sample Moriarty can take any substring of length 3, and it will be equal to the required message u, so Moriarty won't have to make any changes.
In the second sample you should take a substring consisting of characters from second to fourth ("bca") or from fifth to sixth ("bc"). Then you will only have to make one change: to change or to add the last character.
In the third sample the initial string s doesn't contain any character that the message should contain, so, whatever string you choose, you will have to make at least 7 changes to obtain the required message.
题目大意:给你两个串a,b,只能在尾部增删字符,可以在任意位置改变字符,问你最少需要多少次改变,让a中的字串变为b。
解题思路:直接找到最长可以匹配的字符个数,然后最后用len2-ans就是最少需要改动的次数。
#include<stdio.h>
#include<algorithm>
#include<string.h>
#include<math.h>
#include<string>
#include<iostream>
#include<queue>
#include<stack>
#include<map>
#include<vector>
#include<set>
using namespace std;
typedef long long LL;
#define mid (L+R)/2
#define lson rt*2,L,mid
#define rson rt*2+1,mid+1,R
#pragma comment(linker, "/STACK:102400000,102400000")
const int maxn = 1e3 + 300;
const int INF = 0x3f3f3f3f;
typedef long long LL;
typedef unsigned long long ULL;
char s1[maxn*2],s2[maxn*2];
int dp[maxn*2][maxn*2];
int main(){
while(scanf("%s%s",s1+1,s2+1)!=EOF){
int len1, len2;
len1 = strlen(s1+1);
len2 = strlen(s2+1);
int ans = 0;
for(int i = 1; i <= len1; i++){
for(int j = 1; j <= len2; j++){
ans = max(ans, dp[i][j] = dp[i-1][j-1] + (s1[i] == s2[j]) );
}
}
//for(int i = 1; i <= len1; i++){
// for(int j = 1; j <= len2; j++){
// printf("%d ",dp[i][j]);
// }puts("");
// } cout<<len2 - ans<<endl;
}
return 0;
}
Codeforces 156 A——Message——————【思维题】的更多相关文章
- CF--思维练习-- CodeForces - 215C - Crosses(思维题)
ACM思维题训练集合 There is a board with a grid consisting of n rows and m columns, the rows are numbered fr ...
- Codeforces 675C Money Transfers 思维题
原题:http://codeforces.com/contest/675/problem/C 让我们用数组a保存每个银行的余额,因为所有余额的和加起来一定为0,所以我们能把整个数组a划分为几个区间,每 ...
- Codeforces 1090D - Similar Arrays - [思维题][构造题][2018-2019 Russia Open High School Programming Contest Problem D]
题目链接:https://codeforces.com/contest/1090/problem/D Vasya had an array of n integers, each element of ...
- codeforces 1140D(区间dp/思维题)
D. Minimum Triangulation time limit per test 2 seconds memory limit per test 256 megabytes input sta ...
- Codeforces 957 水位标记思维题
A #include <bits/stdc++.h> #define PI acos(-1.0) #define mem(a,b) memset((a),b,sizeof(a)) #def ...
- ACM思维题训练 Section A
题目地址: 选题为入门的Codeforce div2/div1的C题和D题. 题解: A:CF思维联系–CodeForces -214C (拓扑排序+思维+贪心) B:CF–思维练习-- CodeFo ...
- codeforces ~ 1009 B Minimum Ternary String(超级恶心的思维题
http://codeforces.com/problemset/problem/1009/B B. Minimum Ternary String time limit per test 1 seco ...
- 贪心/思维题 Codeforces Round #310 (Div. 2) C. Case of Matryoshkas
题目传送门 /* 题意:套娃娃,可以套一个单独的娃娃,或者把最后面的娃娃取出,最后使得0-1-2-...-(n-1),问最少要几步 贪心/思维题:娃娃的状态:取出+套上(2),套上(1), 已套上(0 ...
- C. Nice Garland Codeforces Round #535 (Div. 3) 思维题
C. Nice Garland time limit per test 1 second memory limit per test 256 megabytes input standard inpu ...
随机推荐
- RabbitMQ.Bus
一个.netcore下的,十分简单的rabbitmq封装,基于RabbitMQ.Client Nuget https://www.nuget.org/packages/RabbitMQ.Bus/ ht ...
- Partition--分区Demo
--============================================================= --创建分区函数 --创建500分区,分区键按照1000依次递增 CRE ...
- [HTTP]Nonocast.http post方法
Nonocast.Http is a free, open source developer focused web service via http for small and medium sof ...
- MSSQL Server中partition by与group by的区别
在使用over等开窗函数时,over里头的分组及排序的执行晚于“where,group by,order by(但此排序顺序优先级是最高的)”的执行. ①group by 列名 合并(列值相同的并作一 ...
- 加密--HashPasswordForStoringInConfigFile过时问题
最近公司在对一套代码进行重构,把原本的web form换成mvc. 刚刚好几天打算开始做下登录,登录则必然会涉及到密码加密的问题. 原本打算用旧的加密方法就行了,哪里知道其中的md5加密出现了这样的问 ...
- c++实验3 链式存储线性表
1.线性表链式存储结构及基本操作算法实现 (1)单链表存储结构类的定义: #include <iostream> using namespace std; template <cla ...
- redis 3.0 集群__配置文件详解(常用配置)
参考文档 http://www.cnblogs.com/huangjacky/p/3700473.html http://www.cnblogs.com/cxd4321/archive/2012/12 ...
- webpack---less+热更新 使用
最近尝试用less写界面,webpack进行打包,然后发现每次修改less时都需要重新执行webpack打包一下,于是就想到了webpack热更新这个功能. 一.使用less less是一门css预处 ...
- 如何高度自定义CollectionView的header和foot
最近在研究CollectionView,突然发现觉得他的HeaderSection和FootSection也可以高度自定义. 国外有详细的教程:http://www.appcoda.com/ios-c ...
- 深入理解计算机系统10——系统级I/O
系统级I/O 输入/输出 是在主存和外部设备之间拷贝数据的过程. 外部设备可以是:磁盘驱动器.终端和网络. 输入和输出都是相对于主存而言的. 输入是从I/O设备拷贝数据到主存.输出时从主存拷贝数据到I ...