A. Message
time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

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.

Input

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.

Output

Print the only integer — the minimum number of changes that Dr. Moriarty has to make with the string that you choose.

Examples
input
aaaaa
aaa
output
0
input
abcabc
bcd
output
1
input
abcdef
klmnopq
output
7
Note

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

  1. 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 ...

  2. 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 ...

  3. 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 ...

  4. 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 ...

  5. 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 ...

  6. 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 ...

  7. 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 ...

  8. 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 ...

  9. 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

  1. 玩转车联网1---初识OBD和行车助手

    题目取得有点大,不免有博取眼球之嫌.车联网作为物联网的一个分支,预计在2015年市场会达到1500亿,特斯拉股票balabala,谷歌无人驾驶, 当然,我们是技术类博客,得找个能够快速上手,快速落地的 ...

  2. Android 打开URL中的网页和拨打电话、发送短信功能

    拨打电话需要的权限 <uses-permission android:name="android.permission.CALL_PHONE"/> 为了省事界面都写一起 ...

  3. mysql 启动提示:错误2系统找不到指定文件

    详情见这个方法 其实就是更改了启动目录导致的 https://blog.csdn.net/su749520/article/details/78963878

  4. iframe嵌套页面的跳转方式

    一.背景A,B,C,D都是jsp,D是C的iframe,C是B的iframe,B是A的iframe,在D中跳转页面的写法区别如下. 二.JS跳转window.location.href.locatio ...

  5. 如何构建debian包

        1)安装dh_make如下: sudo apt-get intasll aptitude sudo aptitude install dh_make    2)以jsoncpp为例,说明如何生 ...

  6. spring quartz 的定时器cronExpression表达式写法(转载)

    转载来源:https://zhidao.baidu.com/question/240797777248343764.html====================================== ...

  7. 2016级算法第二次上机-C.AlvinZH的儿时梦想——坦克篇

    872 AlvinZH的儿时梦想----坦克篇 思路 简单题.仔细看题,题目意在找到直线穿过的矩形数最小,不能从两边穿过.那么我们只要知道每一行矩形之间的空隙位置就可以了. 如果这里用二维数组记住每一 ...

  8. Jquery sblings

    $("给定元素").siblings(".selected") 中的(".selected")表示筛选给定元素类名为.selected的同胞 ...

  9. (USB HID) Report Descriptor 理解

    在這理整理一下基本 Report Descriptor 對於入門基礎的了解. 在很多文件.Blog都有提到HID report 總共分為3種 : Input.Output.Feature report ...

  10. 评估指标:ROC,AUC,Precision、Recall、F1-score

    一.ROC,AUC ROC(Receiver Operating Characteristic)曲线和AUC常被用来评价一个二值分类器(binary classifier)的优劣 . ROC曲线一般的 ...