nefu 88 Moving Tables

本文介绍了一个关于在狭窄走廊中高效移动大量桌子的问题解决方案。通过贪心算法和结构体排序的方法,实现了最小化移动所有桌子所需的时间。具体实现包括对移动路径进行排序并标记已完成的任务,确保同时移动的桌子不会冲突。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

Moving Tables
Problem:88     Time Limit:1000ms     Memory Limit:65536K



Description
The famous ACM (Advanced Computer Maker) Company has rented a floor of a building whose shape is in the following figure.




The floor has 200 rooms each on the north side and south side along the corridor. Recently the Company made a plan to reform its system. The reform includes moving a lot of tables between rooms. Because the corridor is narrow and all the tables are big, only one table can pass through the corridor. Some plan is needed to make the moving efficient. The manager figured out the following plan: Moving a table from a room to another room can be done within 10 minutes. When moving a table from room i to room j, the part of the corridor between the front of room i and the front of room j is used. So, during each 10 minutes, several moving between two rooms not sharing the same part of the corridor will be done simultaneously. To make it clear the manager illustrated the possible cases and impossible cases of simultaneous moving.
 


For each room, at most one table will be either moved in or moved out. Now, the manager seeks out a method to minimize the time to move all the tables. Your job is to write a program to solve the manager’s problem.


Input

The input consists of T test cases. The number of test cases ) (T is given in the first line of the input. Each test case begins with a line containing an integer N , 1<=N<=200 , that represents the number of tables to move. Each of the following N lines contains two positive integers s and t, representing that a table is to move from room number s to room number t (each room number appears at most once in the N lines). From the N+3-rd line, the remaining test cases are listed in the same manner as above.


Output

The output should contain the minimum time in minutes to complete the moving, one per line.


Sample Input



10 20 
30 40 
50 60 
70 80 

1 3 
2 200 

10 100 
20 80 
30 50 


Sample Output

10
20
30


Hint


Source

hdu


思路:贪心,写结构体排序,按照开始排升序,如果开始相同则按照结束排升序;

还要标记用过没用过;注意读入时开始和结束可能需要掉反;

  两层循环 i,j 一遍一遍走,只要满足data[j]无标记,且data[j]的开始大于data[i]的结束,且data[j]的开始为奇数或者data[j]的开始减data[i]的结束不等于1,则该组data[j]满足,做上标记;

  每层i后ans++,注意data[i]已做标记不得ans++,应该直接跳到下一层i循环;

  输出ans*10。


代码:

// 今晚第二滴血,该努力了孩子们。。

// 主要感觉这道题的记录ans++有点意思,循环条件挺多的也挺值得借鉴。。


#include <iostream>
#include <algorithm>


using namespace std;


struct sa
{
    int s,e,blog;
}data[405];


int cmp(const sa &a,const sa &b)
{
    if(a.s==b.s) return a.e<b.e;
    else return a.s<b.s;
}


int main()
{
    int t,n,tmp,ans;


    cin>>t;
    while(t--)
    {
        cin>>n;
        for(int i=0;i<n;i++)
        {
            cin>>data[i].s>>data[i].e;
            data[i].blog=0;
            if(data[i].s>data[i].e)
            {
                tmp=data[i].s;
                data[i].s=data[i].e;
                data[i].e=tmp;
            }
        }
        sort(data,data+n,cmp);
        ans=0;
        for(int i=0;i<n;i++)
        {
            if(data[i].blog==1) continue;
            ans++;
            tmp=i;
            data[i].blog=1;
            for(int j=i+1;j<n;j++)
                if(data[j].blog==0&&data[j].s>data[tmp].e&&(data[j].s%2==1||data[j].s-data[tmp].e!=1))
                {
                    tmp=j;
                    data[j].blog=1;
                }
        }
        cout<<ans*10<<endl;
    }
    return 0;
}

评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值