A. Beru-taxi
time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

Vasiliy lives at point (a, b) of the coordinate plane. He is hurrying up to work so he wants to get out of his house as soon as possible. New app suggested n available Beru-taxi nearby. The i-th taxi is located at point (xi, yi) and moves with a speed vi.

Consider that each of n drivers will move directly to Vasiliy and with a maximum possible speed. Compute the minimum time when Vasiliy will get in any of Beru-taxi cars.

Input

The first line of the input contains two integers a and b ( - 100 ≤ a, b ≤ 100) — coordinates of Vasiliy's home.

The second line contains a single integer n (1 ≤ n ≤ 1000) — the number of available Beru-taxi cars nearby.

The i-th of the following n lines contains three integers xi, yi and vi ( - 100 ≤ xi, yi ≤ 100, 1 ≤ vi ≤ 100) — the coordinates of the i-th car and its speed.

It's allowed that several cars are located at the same point. Also, cars may be located at exactly the same point where Vasiliy lives.

Output

Print a single real value — the minimum time Vasiliy needs to get in any of the Beru-taxi cars. You answer will be considered correct if its absolute or relative error does not exceed 10 - 6.

Namely: let's assume that your answer is a, and the answer of the jury is b. The checker program will consider your answer correct, if .

Examples
Input
0 0
2
2 0 1
0 2 2
Output
1.00000000000000000000
Input
1 3
3
3 3 2
-2 3 6
-2 7 10
Output
0.50000000000000000000
Note

In the first sample, first taxi will get to Vasiliy in time 2, and second will do this in time 1, therefore 1 is the answer.

In the second sample, cars 2 and 3 will arrive simultaneously.

题意:给你一个你当前的位置(a,b),给你n个出租车的位置和速度(xi,yi,vi),求某个出租车到你的最短时间;

思路:直接暴力就是;

#include<bits/stdc++.h>
using namespace std;
#define ll __int64
#define esp 1e-10
const int N=3e5+,M=1e6+,mod=1e9+,inf=1e9+;
double jilu(double a,double b,double c,double d)
{
return sqrt((d-b)*(d-b)+(c-a)*(c-a));
}
int main()
{
int x,y,z,i,t;
double a,b;
scanf("%lf%lf",&a,&b);
scanf("%d",&x);
double ans=1000000000.0;
while(x--)
{
double xi,yi,vi;
scanf("%lf%lf%lf",&xi,&yi,&vi);
ans=min(ans,jilu(xi,yi,a,b)/vi);
}
printf("%f\n",ans);
return ;
}
B. Interesting drink
time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Vasiliy likes to rest after a hard work, so you may often meet him in some bar nearby. As all programmers do, he loves the famous drink "Beecola", which can be bought in n different shops in the city. It's known that the price of one bottle in the shop i is equal to xi coins.

Vasiliy plans to buy his favorite drink for q consecutive days. He knows, that on the i-th day he will be able to spent mi coins. Now, for each of the days he want to know in how many different shops he can buy a bottle of "Beecola".

Input

The first line of the input contains a single integer n (1 ≤ n ≤ 100 000) — the number of shops in the city that sell Vasiliy's favourite drink.

The second line contains n integers xi (1 ≤ xi ≤ 100 000) — prices of the bottles of the drink in the i-th shop.

The third line contains a single integer q (1 ≤ q ≤ 100 000) — the number of days Vasiliy plans to buy the drink.

Then follow q lines each containing one integer mi (1 ≤ mi ≤ 109) — the number of coins Vasiliy can spent on the i-th day.

Output

Print q integers. The i-th of them should be equal to the number of shops where Vasiliy will be able to buy a bottle of the drink on the i-th day.

Example
Input
5
3 10 8 6 11
4
1
10
3
11
Output
0
4
1
5
Note

On the first day, Vasiliy won't be able to buy a drink in any of the shops.

On the second day, Vasiliy can buy a drink in the shops 1, 2, 3 and 4.

On the third day, Vasiliy can buy a drink only in the shop number 1.

Finally, on the last day Vasiliy can buy a drink in any shop.

题意:给你一个数组,q个询问,求小于等于mi的数的个数;

思路:二分查找;

#include<bits/stdc++.h>
using namespace std;
#define ll __int64
#define esp 1e-10
const int N=3e5+,M=1e6+,mod=1e9+,inf=1e9+;
int a[N];
int main()
{
int x,y,z,i,t;
scanf("%d",&x);
for(i=;i<x;i++)
scanf("%d",&a[i]);
sort(a,a+x);
scanf("%d",&y);
while(y--)
{
scanf("%d",&z);
int pos=upper_bound(a,a+x,z)-a;
printf("%d\n",pos);
}
return ;
}
C. Hard problem
time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

Vasiliy is fond of solving different tasks. Today he found one he wasn't able to solve himself, so he asks you to help.

Vasiliy is given n strings consisting of lowercase English letters. He wants them to be sorted in lexicographical order (as in the dictionary), but he is not allowed to swap any of them. The only operation he is allowed to do is to reverse any of them (first character becomes last, second becomes one before last and so on).

To reverse the i-th string Vasiliy has to spent ci units of energy. He is interested in the minimum amount of energy he has to spent in order to have strings sorted in lexicographical order.

String A is lexicographically smaller than string B if it is shorter than B (|A| < |B|) and is its prefix, or if none of them is a prefix of the other and at the first position where they differ character in A is smaller than the character in B.

For the purpose of this problem, two equal strings nearby do not break the condition of sequence being sorted lexicographically.

Input

The first line of the input contains a single integer n (2 ≤ n ≤ 100 000) — the number of strings.

The second line contains n integers ci (0 ≤ ci ≤ 109), the i-th of them is equal to the amount of energy Vasiliy has to spent in order to reverse the i-th string.

Then follow n lines, each containing a string consisting of lowercase English letters. The total length of these strings doesn't exceed 100 000.

Output

If it is impossible to reverse some of the strings such that they will be located in lexicographical order, print  - 1. Otherwise, print the minimum total amount of energy Vasiliy has to spent.

Examples
Input
2
1 2
ba
ac
Output
1
Input
3
1 3 1
aa
ba
ac
Output
1
Input
2
5 5
bbb
aaa
Output
-1
Input
2
3 3
aaa
aa
Output
-1
Note

In the second sample one has to reverse string 2 or string 3. To amount of energy required to reverse the string 3 is smaller.

In the third sample, both strings do not change after reverse and they go in the wrong order, so the answer is  - 1.

In the fourth sample, both strings consists of characters 'a' only, but in the sorted order string "aa" should go before string "aaa", thus the answer is  - 1.

题意:n个字符串,第i个字符串要翻转需要花费a[i],使得最后的字符串成字典序排列,求最小花费,始终不行输出-1;

思路:dp,dp[i][0]表示第i个字符串不翻转成字典序排列的花费,dp[i][1]表示第i个字符串翻转成字典序排列的花费;

#include<bits/stdc++.h>
using namespace std;
#define ll __int64
#define mod 1000000007
#define pi (4*atan(1.0))
const int N=1e5+,M=2e6+,inf=1e9+;
const ll INF=1e17;
ll dp[N][];
string str1[N];
string str2[N];
ll a[N];
void init()
{
for(int i=;i<N;i++)
dp[i][]=dp[i][]=INF;
}
int main()
{
int x,y,z,i,t;
init();
scanf("%d",&x);
for(i=;i<=x;i++)
scanf("%I64d",&a[i]);
for(i=;i<=x;i++)
{
cin>>str1[i];
str2[i]=str1[i];
reverse(str2[i].begin(),str2[i].end());
}
dp[][]=;
dp[][]=a[];
for(i=;i<=x;i++)
{
if(str1[i]>=str1[i-])
dp[i][]=min(dp[i][],dp[i-][]);
if(str1[i]>=str2[i-])
dp[i][]=min(dp[i][],dp[i-][]);
if(str2[i]>=str1[i-])
dp[i][]=min(dp[i][],dp[i-][]+a[i]);
if(str2[i]>=str2[i-])
dp[i][]=min(dp[i][],dp[i-][]+a[i]);
}
ll ans=min(dp[x][],dp[x][]);
if(ans<INF)
printf("%I64d\n",ans);
else
printf("-1\n");
return ;
}

Codeforces Round #367 (Div. 2) A , B , C的更多相关文章

  1. Codeforces Round #367 (Div. 2) D. Vasiliy's Multiset (0/1-Trie树)

    Vasiliy's Multiset 题目链接: http://codeforces.com/contest/706/problem/D Description Author has gone out ...

  2. Codeforces Round #367 (Div. 2) C. Hard problem(DP)

    Hard problem 题目链接: http://codeforces.com/contest/706/problem/C Description Vasiliy is fond of solvin ...

  3. Codeforces Round #367 (Div. 2) B. Interesting drink (模拟)

    Interesting drink 题目链接: http://codeforces.com/contest/706/problem/B Description Vasiliy likes to res ...

  4. Codeforces Round #367 (Div. 2) A. Beru-taxi (水题)

    Beru-taxi 题目链接: http://codeforces.com/contest/706/problem/A Description Vasiliy lives at point (a, b ...

  5. Codeforces Round #367 (Div. 2) D. Vasiliy's Multiset

    题目链接:Codeforces Round #367 (Div. 2) D. Vasiliy's Multiset 题意: 给你一些操作,往一个集合插入和删除一些数,然后?x让你找出与x异或后的最大值 ...

  6. Codeforces Round #367 (Div. 2) C. Hard problem

    题目链接:Codeforces Round #367 (Div. 2) C. Hard problem 题意: 给你一些字符串,字符串可以倒置,如果要倒置,就会消耗vi的能量,问你花最少的能量将这些字 ...

  7. Codeforces Round #367 (Div. 2) (A,B,C,D,E)

    Codeforces Round 367 Div. 2 点击打开链接 A. Beru-taxi (1s, 256MB) 题目大意:在平面上 \(n\) 个点 \((x_i,y_i)\) 上有出租车,每 ...

  8. Codeforces Round #367 (Div. 2) D. Vasiliy's Multiset(01字典树求最大异或值)

    http://codeforces.com/contest/706/problem/D 题意:有多种操作,操作1为在字典中加入x这个数,操作2为从字典中删除x这个数,操作3为从字典中找出一个数使得与给 ...

  9. Codeforces Round #367 (Div. 2) D. Vasiliy's Multiset Trie

    题目链接: http://codeforces.com/contest/706/problem/D D. Vasiliy's Multiset time limit per test:4 second ...

  10. Codeforces Round #367 (Div. 2)

    A题 Beru-taxi 随便搞搞.. #include <cstdio> #include <cmath> using namespace std; int a,b,n; s ...

随机推荐

  1. 新提交审核app保留检查更新入口将被拒绝

    3月起要求关闭所有App内的检查更新功能,苹果App Store将向用户自动提示更新,新提交审核版本如果保留检查更新入口审核时将被拒绝,请各产品团队重点关注. 10.6 - Apple and our ...

  2. commit Commit changes to stable storage 对变化提交

    Python36\site-packages\pymysql\connections.py # Python implementation of the MySQL client-server pro ...

  3. 使用QtConcurrent编写多线程程序(也可以阻塞)

    版权声明:本文为博主原创文章,未经博主允许不得转载. https://blog.csdn.net/Amnes1a/article/details/66470751Qt在其QtConcurrent命名空 ...

  4. 我的Android进阶之旅------>解决Bug:打开eclipse报错,发现了以元素 'd:skin' 开头的无效内容。此处不应含有子元素。

    今天来打开Eclipse 报错了,错误信息如下: [2015-08-01 09:07:43 - Android SDK] Error when loading the SDK: Error: Erro ...

  5. 测试开发面试的Linux面试题:常用命令

    Hello,大家好上次给大家介绍了vim使用方法,今天来给大家讲一讲linux系统文件命令 (1)Linux的文件系统目录配置要遵循FHS规范,规范定义的两级目录规范如下:        /home  ...

  6. centos7 安装vue

    1: npm安装: 2: 报错:  bash: vue: command not found 执行npm install --global vue-cli 后 执行 vue 报错 bash: vue: ...

  7. SQL SERVER 2005 Express版, 精简版 下载

      Microsoft SQL Server 2005 Express Edition(数据库) https://www.microsoft.com/zh-CN/download/details.as ...

  8. PDO:数据访问抽象层

    <?php //PDO:数据访问抽象层 //带有事务功能: //dsn:数据源 $dsn="mysql:host=localhost;dbname=aaas"; //造pdo ...

  9. Funq之Lambda表达式2

    Last month I started a series of posts covering some of the new VB and C# language features that are ...

  10. Service Fusing

    服务熔断也称服务隔离,来自于Michael Nygard 的<Release It>中的CircuitBreaker应用模式,Martin Fowler在博文CircuitBreaker中 ...