HDU 1026 Ignatius and the Princess I

单纯bfs问题。

左上角是入口迷宫，右下角是出口，有战斗在迷宫1~9后卫，他们需要击败1~9时间。

遇到怪物就能判断是什么。步骤反向输出可。

因为需要记录的步骤，队列了。

也能够使用priority_queue 优化到 0ms，

模拟queue

#include<cstdio>
#include<cstring>
#include<string>
#include<queue>
#include<algorithm>
#include<map>
#include<stack>
#include<iostream>
#include<list>
#include<set>
#include<vector>
#include<cmath>

#define INF 0x7fffffff
#define eps 1e-8
#define LL long long
#define PI 3.141592654
#define CLR(a,b) memset(a,b,sizeof(a))
#define FOR(i,a,n) for(int i= a;i< n ;i++)
#define debug puts("==fuck==")
#define acfun std::ios::sync_with_stdio(false)

#define SIZE 1000+10
using namespace std;

int xx[]={0,0,-1,1};
int yy[]={-1,1,0,0};
int n,m;
char g[101][101];
struct lx
{
    int x,y,lv,path;
    void init(int xx,int yy,int llv,int p)
    {
        x=xx,y=yy,lv=llv,path=p;
    }
};
lx q[10000001];
void bfs()
{
    bool vis[101][101];
    CLR(vis,0);
    vis[0][0]=1;
    lx tmp;
    tmp.init(0,0,0,-1);
    int h=0,e=0;
    q[h++]=tmp;
    bool flag=0;
    while(e<h)
    {
        tmp=q[e++];
        lx now;
//        printf("%d %d ==%d\n",tmp.x,tmp.y,tmp.lv);
//        system("pause");
        if(tmp.x==n-1&&tmp.y==m-1&&(g[tmp.x][tmp.y]<'1'||g[tmp.x][tmp.y]>'9'))
        {
            flag=1;
            break;
        }
        if(g[tmp.x][tmp.y]>='1'&&g[tmp.x][tmp.y]<='9')
        {
            now.init(tmp.x,tmp.y,tmp.lv+1,e-1);
            g[tmp.x][tmp.y]--;
            vis[tmp.x][tmp.y]=1;
            q[h++]=now;
        }
        else
        FOR(k,0,4)
        {
            int x=tmp.x+xx[k];
            int y=tmp.y+yy[k];
            if(x<0||y<0||x>=n||y>=m||vis[x][y]||g[x][y]=='X')
                continue;
            now.init(x,y,tmp.lv+1,e-1);
            vis[x][y]=1;
            q[h++]=now;
        }
    }
    if(flag)
    {
        stack<lx>out;
        out.push(tmp);
        int path=tmp.path;
        int t=tmp.lv;
        while(path!=-1)
        {
            out.push(q[path]);
            path=q[path].path;
        }
        printf("It takes %d seconds to reach the target position, let me show you the way.\n",t);
        while(!out.empty())
        {
            lx now=out.top();out.pop();
            if(now.lv==0)
            {
                tmp=now;
                continue;
            }
            if(now.x==tmp.x&&now.y==tmp.y)
                printf("%ds:FIGHT AT (%d,%d)\n",now.lv,now.x,now.y);
            else
                printf("%ds:(%d,%d)->(%d,%d)\n",now.lv,tmp.x,tmp.y,now.x,now.y);
            tmp=now;

        }
    }
    else
        puts("God please help our poor hero.");
    puts("FINISH");
}

int main()
{
    while(~scanf("%d%d",&n,&m))
    {
        char str[101];
        FOR(i,0,n)
        {
            scanf("%s",str);
            FOR(j,0,m)
            g[i][j]=str[j];
        }
        bfs();
    }
}

priority_queue版本号

#include<cstdio>
#include<cstring>
#include<string>
#include<queue>
#include<algorithm>
#include<map>
#include<stack>
#include<iostream>
#include<list>
#include<set>
#include<vector>
#include<cmath>

#define INF 0x7fffffff
#define eps 1e-8
#define LL long long
#define PI 3.141592654
#define CLR(a,b) memset(a,b,sizeof(a))
#define FOR(i,a,n) for(int i= a;i< n ;i++)
#define debug puts("==fuck==")
#define acfun std::ios::sync_with_stdio(false)

#define SIZE 100+10
using namespace std;

int xx[]={0,0,-1,1};
int yy[]={-1,1,0,0};
int n,m;
char g[SIZE][SIZE];
struct lx
{
    int x,y,lv,path,now;
    void init(int xx,int yy,int llv,int p,int n)
    {
        x=xx,y=yy,lv=llv,path=p,now=n;
    }
    friend bool operator< (lx a,lx b)
    {
        return a.lv>b.lv;
    }
}que[10100];
lx start;

void bfs()
{
    priority_queue<lx>q;
    start.init(0,0,0,-1,0);
    bool vis[SIZE][SIZE];
    CLR(vis,0);
    vis[0][0]=1;
    int h=0;
    que[h++]=start;
    q.push(start);
    bool flag=0;
    lx tmp;
    while(!q.empty())
    {
        tmp=q.top();
        q.pop();
//        printf("%d %d==%d\n",tmp.x,tmp.y,tmp.lv);
//        system("pause");
        if(tmp.x==n-1&&tmp.y==m-1)
        {
            flag=1;
            break;
        }
        FOR(k,0,4)
        {
            int x=tmp.x+xx[k];
            int y=tmp.y+yy[k];
            if(x<0||y<0||x>=n||y>=m||g[x][y]=='X'||vis[x][y])
                continue;
            if(g[x][y]>='1'&&g[x][y]<='9')
                que[h].init(x,y,tmp.lv+g[x][y]-'0'+1,tmp.now,h);
            else
                que[h].init(x,y,tmp.lv+1,tmp.now,h);
            q.push(que[h++]);
            vis[x][y]=1;
        }
    }
    if(flag)
    {
        printf("It takes %d seconds to reach the target position, let me show you the way.\n",tmp.lv);
        stack<lx>out;
        int path=tmp.now;
        while(path!=-1)
        {
            out.push(tmp);
            path=tmp.path;
            tmp=que[path];
        }
        lx now;
        while(!out.empty())
        {
            tmp=out.top();
            out.pop();
            if(tmp.lv==0)
            {
                now=tmp;
                continue;
            }
            if(tmp.lv-now.lv==1)
                printf("%ds:(%d,%d)->(%d,%d)\n",tmp.lv,now.x,now.y,tmp.x,tmp.y);
            else
            {
                printf("%ds:(%d,%d)->(%d,%d)\n",++now.lv,now.x,now.y,tmp.x,tmp.y);
                while(now.lv++<tmp.lv)
                    printf("%ds:FIGHT AT (%d,%d)\n",now.lv,tmp.x,tmp.y);
            }
            now=tmp;
        }
    }
    else
        puts("God please help our poor hero.");
    puts("FINISH");
}

int main()
{
    while(~scanf("%d%d",&n,&m))
    {
        char str[SIZE];
        FOR(i,0,n)
        {
            scanf("%s",str);
            FOR(j,0,m)
            {
                g[i][j]=str[j];
            }
        }
        bfs();
    }
}