HDOJ1242(延时迷宫BFS)

#include<iostream>
#include<cstdio>
#include<queue>
using namespace std;
const int MAX_N=205;
const int INF=0x30303030;
char map[MAX_N][MAX_N];
int N,M;
int sx,sy;
int gx,gy;
int dx[4]={1, 0, -1, 0};
int dy[4]={0, 1, 0, -1};
typedef pair<int, int> P;
int dist[MAX_N][MAX_N];
int bfs(int y, int x)
{
    for(int i=0; i<N; i++)
        for(int j=0; j<M; j++)
            dist[i][j]=INF;
    dist[sy][sx]=0;
    queue<P> que;
    que.push(P(sy,sx));
    
    while(!que.empty())
    {
        P pos=que.front();que.pop();
        int y=pos.first;
        int x=pos.second;
        if(y==gy&&x==gx)
        {
            break;
        }
        for(int i=0; i<4; i++)
        {
            int ny=y+dy[i];
            int nx=x+dx[i];
            if(0<=ny&&ny<N&&0<=nx&&nx<M&&map[ny][nx]!=‘#‘)
            {
                int d;
                if(map[ny][nx]==‘x‘)
                {
                    d=dist[y][x]+2;
                }
                else
                {
                    d=dist[y][x]+1;
                }
                if(d>=dist[ny][nx])
                {
                    continue;
                }
                dist[ny][nx]=d;    
                que.push(P(ny,nx));
            }
        }
        
    }
    return dist[gy][gx];
}


int main()
{
   while(cin>>N>>M)
   {
        for(int i=0; i<N; i++)
        {
            for(int j=0; j<M; j++)
            {
                cin>>map[i][j];
                if(map[i][j]==‘r‘)
                {
                    sy=i;
                    sx=j;
                }
                if(map[i][j]==‘a‘)
                {
                    gy=i;
                    gx=j;
                }
            }
        }
    
        int exist=bfs(sy,sx);
        if(exist==INF)
        {
            cout<<"Poor ANGEL has to stay in the prison all his life."<<endl;
        }
        else
        {
            cout<<exist<<endl;
        }
    }
    return 0;
}

#include"iostream"
#include"queue"
using namespace std;
const int INF=0x30303030;
const int MAX_N=205;
int N, M;
char map[MAX_N][MAX_N];
int sy, sx;
int gx, gy;
int dx[4]={1, 0, -1, 0};
int dy[4]={0, 1, 0, -1};
int d[MAX_N][MAX_N];
struct node{
    int y;
    int x;
    int step;
    node(int y, int x, int step)
    {
        this->y=y;
        this->x=x;
        this->step=step;
    }
friend bool operator<(node no1, node no2)
        {
            return no1.step > no2.step;
        }
};

void dfs()
{
    for(int i=0; i<N; i++)
    {
        for(int j=0; j<M; j++)
        {
            d[i][j]=INF;
        }
    }
    
    int ans;
    bool exist=false;
    priority_queue<node> que;
    que.push(node(sy,sx,0));
    while(!que.empty())
    {
        node now=que.top();que.pop();
        if(now.y==gy&&now.x==gx)
        {
            ans=now.step;
            exist=true;
            break;
        }
        for(int i=0; i<4; i++)
        {
            int ny=now.y+dy[i];
            int nx=now.x+dx[i];
            if(0<=ny&&ny<N&&0<=nx&&nx<M&&map[ny][nx]!=‘#‘)
            {
                int dist;
                if(map[ny][nx]==‘x‘)
                {
                    dist=now.step+2;
                }
                else
                {
                    dist=now.step+1;
                }
                if(dist>=d[ny][nx])    continue;
                d[ny][nx]=dist;
                que.push(node(ny,nx,dist));
            }
        }
    }
    
    if(exist)
    {
        cout<<ans<<endl;
    }
    else
    {
        cout<<"Poor ANGEL has to stay in the prison all his life."<<endl;
    }
}

int main()
{
    while(cin>>N>>M)
    {
        for(int i=0; i<N; i++)
        {
            for(int j=0; j<M; j++)
            {
                cin>>map[i][j];
                if(map[i][j]==‘r‘)
                {
                    sy=i;
                    sx=j;
                }
                if(map[i][j]==‘a‘)
                {
                    gy=i;
                    gx=j;
                }
            }
        }
        dfs();
    }
        
    return 0;
}