hdu 1026 Ignatius and the Princess I

普通广搜而已，只不过队列是优先队列，以时间为key

#include <stdio.h>
#include <string.h>
#include <queue>

 

using namespace std;

 

#define MAXSIZE 110

 

struct qnode
{
    int x,y,time;
    bool operator<(const qnode &e) const
    {
        //最小堆
        return e.time<time;
    }
};
priority_queue <qnode> que;

struct path_node
{
    int prex,prey;
};
path_node path[MAXSIZE][MAXSIZE];

int seconds,N,M,dir[4][2]= {{0,1},{1,0},{0,-1},{-1,0}};
char maze[MAXSIZE][MAXSIZE];
bool visited[MAXSIZE][MAXSIZE];

bool bfs()
{
    while( !que.empty() ) que.pop();
    qnode cur,next;
    cur.x=N-1;
    cur.y=M-1;
    if(maze[N-1][M-1]=='.') cur.time=0;
    else cur.time=maze[N-1][M-1]-'0';
    que.push(cur);
    visited[N-1][M-1]=true;
    path[N-1][M-1].prex=path[N-1][M-1].prey=-1;
    int i,j,k;
    while(!que.empty())
    {
        cur=que.top();
        if(cur.x==0 && cur.y==0)
        {
            seconds=cur.time;
            return true;
        }
        que.pop();
        for(k=0; k<4; k++)
        {
            i=cur.x+dir[k][0];
            j=cur.y+dir[k][1];
            if(i<0 || i>=N || j<0 || j>=M || visited[i][j] || maze[i][j]=='X') continue;
            if(maze[i][j]=='.')
            {
                next.x=i;
                next.y=j;
                next.time=cur.time+1;
                que.push(next);
            }
            else
            {
                next.x=i;
                next.y=j;
                next.time=cur.time+1 + maze[i][j]-'0';
                que.push(next);
            }
            path[i][j].prex=cur.x;
            path[i][j].prey=cur.y;
            visited[i][j]=true;
        }
    }
    return false;
}

void printpath()
{
    printf("It takes %d seconds to reach the target position, let me show you the way.\n",seconds);
    int i=0,j=0,k,ti,tj;
    seconds=1;
    if(maze[0][0]!='.')
    {
        k=maze[0][0]-'0';
        while(k--)
        {
            printf("%ds:FIGHT AT (%d,%d)\n",seconds,i,j);
            seconds++;
        }
    }
    while(path[i][j].prex != -1)
    {
        ti=i;
        tj=j;
        i=path[ti][tj].prex;
        j=path[ti][tj].prey;
        printf("%ds:(%d,%d)->(%d,%d)\n",seconds,ti,tj,i,j);
        if(maze[i][j]!='.')
        {
            k=maze[i][j]-'0';
            while(k--)
            {
                seconds++;
                printf("%ds:FIGHT AT (%d,%d)\n",seconds,i,j);
            }
        }
        seconds++;
    }
    printf("FINISH\n");
}

int main()
{
    while(scanf("%d%d",&N,&M)!=EOF)
    {
        getchar();
        int i,j;
        for(i=0; i<N; i++)
        {
            for(j=0; j<M; j++)
                scanf("%c",&maze[i][j]);
            getchar();
        }
        memset(visited,0,sizeof(visited));
        if( bfs() ) printpath();
        else printf("God please help our poor hero.\nFINISH\n");
    }
    return 0;
}