1817:城堡问题

#include <iostream>
using namespace std;
int southNorth, westEast;
int castle[55][55];
int vis[55][55];
int roomNum;
int roomSize;
int maxRoomSize=0;
//1表示西墙，2表示北墙，4表示东墙，8表示南墙
int goSouthNorth[4]={0,-1,0,1};
int goWestEast[4]={-1,0,1,0};

void init() {
    //1、读数据
    cin >> southNorth >> westEast;
    for (int i = 1; i <= southNorth; i++) {
        for (int j = 1; j <= westEast; j++) {
            cin >> castle[i][j];
            vis[i][j]=false;
        }
    }
    //2、变量初始化
    roomNum=0;

}

void print() {
    cout<< southNorth <<" "<< westEast<<endl;
    for (int i = 1; i <= southNorth; i++) {
        for (int j = 1; j <= westEast; j++) {
            cout<< castle[i][j]<<" ";
        }
        cout<<endl;
    }
}

void printAns(){
    cout<<roomNum<<endl<<maxRoomSize<<endl;
}
//把一个房间所有能访问的格子都给它访问了
void searchAll(int startH,int startW){
    for(int i=0;i<4;i++){
        //b1为true说明有墙，不能走
        bool b1=(1<<i)&castle[startH][startW];
        if(!b1){//如果没墙能走
            int h1=startH+goSouthNorth[i];
            int w1=startW+goWestEast[i];
            //b2是不越界
            bool b2= h1>=1&&h1<=southNorth&&w1>=1&&w1<=westEast;
            if(b2&&!vis[h1][w1]){//如果不越界并且没有被访问过
                vis[h1][w1]=true;
                roomSize++;
                if(roomSize>maxRoomSize) maxRoomSize=roomSize;
                searchAll(h1,w1);
            }
        }
    }
}

void search(){
    for (int i = 1; i <= southNorth; i++) {
            for (int j = 1; j <= westEast; j++) {
                roomSize=0;
                if(!vis[i][j]){
                    vis[i][j]=true;
                    roomNum++;
                    roomSize++;
                    //cout<<"roomNum:"<<"i="<<i<<" j="<<j<<endl;
                    searchAll(i,j);
                }
            }
        }
}

int main() {
    //freopen("1817in.txt","r",stdin);
    init();
    //print();
    search();
    printAns();
    return 0;
}