• 2015-2016 ACM-ICPC, NEERC, Southern Subregional Contest J Cleaner Robot


    Cleaner RobotCrawling in process... Crawling failed Time Limit:2000MS     Memory Limit:524288KB     64bit IO Format:%I64d & %I64u

    Submit Status

    Description

     

    Input

     

    Output

     

    Sample Input

     

    Sample Output

     

    Hint

     

    Description

    Masha has recently bought a cleaner robot, it can clean a floor without anybody's assistance.

    Schematically Masha's room is a rectangle, consisting of w × h square cells of size 1 × 1. Each cell of the room is either empty (represented by character '.'), or occupied by furniture (represented by character '*').

    A cleaner robot fully occupies one free cell. Also the robot has a current direction (one of four options), we will say that it looks in this direction.

    The algorithm for the robot to move and clean the floor in the room is as follows:

    1. clean the current cell which a cleaner robot is in;
    2. if the side-adjacent cell in the direction where the robot is looking exists and is empty, move to it and go to step 1;
    3. otherwise turn 90 degrees clockwise (to the right relative to its current direction) and move to step 2.

    The cleaner robot will follow this algorithm until Masha switches it off.

    You know the position of furniture in Masha's room, the initial position and the direction of the cleaner robot. Can you calculate the total area of the room that the robot will clean if it works infinitely?

    Input

    The first line of the input contains two integers, w and h (1 ≤ w, h ≤ 10) — the sizes of Masha's room.

    Next w lines contain h characters each — the description of the room. If a cell of a room is empty, then the corresponding character equals '.'. If a cell of a room is occupied by furniture, then the corresponding character equals '*'. If a cell has the robot, then it is empty, and the corresponding character in the input equals 'U', 'R', 'D' or 'L', where the letter represents the direction of the cleaner robot. Letter 'U' shows that the robot is looking up according to the scheme of the room, letter 'R' means it is looking to the right, letter 'D' means it is looking down and letter 'L' means it is looking to the left.

    It is guaranteed that in the given w lines letter 'U', 'R', 'D' or 'L' occurs exactly once. The cell where the robot initially stands is empty (doesn't have any furniture).

    Output

    In the first line of the output print a single integer — the total area of the room that the robot will clean if it works infinitely.

    Sample Input

     
    Input
    2 3
    U..
    .*.
    Output
    4
    Input
    4 4
    R...
    .**.
    .**.
    ....
    Output
    12
    Input
    3 4
    ***D
    ..*.
    *...
    Output
    6

    Sample Output

     

    Hint

    In the first sample the robot first tries to move upwards, it can't do it, so it turns right. Then it makes two steps to the right, meets a wall and turns downwards. It moves down, unfortunately tries moving left and locks itself moving from cell (1, 3) to cell (2, 3) and back. The cells visited by the robot are marked gray on the picture.

                                                                                                                 

    /*
    一个机器人遇到障碍物就会顺时针旋转90度,问你机器人活动区域最大是多少
    用v[i][j][d]记录用怎么样的状态进入这个点,如果下一次又出现,那么一定出现循环就可以停止了
    */
    
    #include<bits/stdc++.h> 
    #include<string.h>
    #include<stdio.h>
    #define N 12
    using namespace std; 
    int n,m,cur=1;
    int dir[5][2]={-1,0,1,0,0,-1,0,1};//上下左右
    char mapn[N][N];
    int visit[N][N]={0};//记录这个点来没来过
    int visitn[N][N][N]={0};//记录这个点来过多少次
    int v(char ch)
    {
        if(ch=='U') return 0;
        if(ch=='D') return 1;
        if(ch=='L') return 2;
        if(ch=='R') return 3;
    }
    bool check(int x1,int y1)
    {
        if(x1<0||x1>=n||y1<0||y1>=m||mapn[x1][y1]=='*')
            return true;
        return false;
    }
    void dfs(int x,int y,int d)
    {
        if(visitn[x][y][d])
            return ;
        visitn[x][y][d]=1;
        if(!visit[x][y])
            cur++,visit[x][y]=1;
        if(d==0)//
        {
            int fx=x+dir[0][0];
            int fy=y+dir[0][1];
            if(check(fx,fy))//走不通
                //cout<<"转向 "<<x<<" "<<y<<endl;
                dfs(x,y,3);
            else//能走通
                dfs(fx,fy,0);
        }
        else if(d==1)//
        {
            int fx=x+dir[1][0];
            int fy=y+dir[1][1];
            if(check(fx,fy))//走不通
                //cout<<"转向 "<<x<<" "<<y<<endl;
                dfs(x,y,2);
            else//能走通
                dfs(fx,fy,1);
        }
        else if(d==2)//
        {
            int fx=x+dir[2][0];
            int fy=y+dir[2][1];
            //cout<<x<<" "<<y<<endl;
            //cout<<fx<<" "<<fy<<endl;
            //return ;
            if(check(fx,fy))//走不通
                //cout<<"转向 "<<x<<" "<<y<<endl;
                dfs(x,y,0);
            else//能走通
                dfs(fx,fy,2);
        }
        else if(d==3)//
        {
            int fx=x+dir[3][0];
            int fy=y+dir[3][1];
            if(check(fx,fy))//走不通
                //cout<<"转向 "<<x<<" "<<y<<endl;
                dfs(x,y,1);
            else//能走通
                dfs(fx,fy,3);
        }
    }
    int main()
    { 
        //freopen("in.txt","r",stdin);
        scanf("%d%d",&n,&m);
        //cout<<n<<" "<<m<<endl;
            getchar();
            int x,y;
            cur=1;
            for(int i=0;i<n;i++)
            {
                for(int j=0;j<m;j++)
                {
                    scanf("%c",&mapn[i][j]);
                    if(mapn[i][j]=='U'||mapn[i][j]=='D'||mapn[i][j]=='L'||mapn[i][j]=='R')
                        x=i,y=j;
                }
                scanf("
    ");
            }
            //for(int i=0;i<n;i++)
            //    cout<<mapn[i]<<endl;
            visit[x][y]=1;
            dfs(x,y,v(mapn[x][y]));
            //for(int i=0;i<n;i++)
            //{
            //    for(int j=0;j<m;j++)
            //        cout<<visit[i][j]<<" ";
            //    cout<<endl;
            //}
            printf("%d
    ",cur);
        return 0; 
    } 
  • 相关阅读:
    利用同步辅助类CountDownLatch计算多线程的运行时间
    i++的原子性问题
    Volatile关键字以及线程的内存可见性问题
    创建线程的第三种方式以及简单使用
    java8新特性-lambda表达式和stream API的简单使用
    springboot整合activemq
    springboot整合redis单机及集群
    JAVA-基础(一)
    CentOS-文件操作
    理解AngularJS的作用域Scope
  • 原文地址:https://www.cnblogs.com/wuwangchuxin0924/p/5791131.html
Copyright © 2020-2023  润新知