hdu 4308 Saving Princess claire_

http://acm.hdu.edu.cn/showproblem.php?pid=4308
 题解：

 最短路，将p看成一个点

 dij（）硬是tle 我就奇怪了 最多就5000*5000啊，；最后该的SPFA（）1A  。。。。。。。

#include<stdio.h>

#include<string.h>

#include<iostream>

#include<vector>

using namespace std;

#define maxn 5001

#define inf 999999

#define CL(V,num) memset(V,num,sizeof(V));

char str[maxn][maxn];



int r,c,cost,max1,p,s,e;

int dis[maxn],vis[maxn];

int find(int x,int y)

{



      return x*c+y;

}

struct node

{

    int k;

    int l;

};

vector<node>g[maxn];

int queue[maxn*200+10];

void build()

{



    int i,j;

      int x,y;

      node a;

    for(i=0;i<r;i++)

    {

        for(j=0;j<c;j++)

        {



            if(str[i][j]!='#')

            {

                if(str[i][j]=='P')

                {

                    if(p==-1)

                      p=find(i,j);



                     x=p;



                }

                else    x=find(i,j);

                max1=max1>x?max1:x;





                if(str[i][j]=='Y')s=x;

                if(str[i][j]=='C')e=x;

                if(i-1>=0&&str[i-1][j]!='#')

                {

                    if(str[i-1][j]=='P'&&p==-1)p=find(i-1,j);//将p看成一个点

                    if(str[i-1][j]=='P'&&p!=-1)y=p;

                    else

                       y=find(i-1,j);

                    a.k=y;

                    if(str[i-1][j]=='*')

                       a.l=cost;

                    else a.l=0;

                    g[x].push_back(a);

                }

                if(j+1<c&&str[i][j+1]!='#')

                {

                    if(str[i][j+1]=='P'&&p==-1)p=find(i,j+1);

                    if(str[i][j+1]=='P'&&p!=-1)y=p;

                    else

                      y=find(i,j+1);

                    a.k=y;

                    if(str[i][j+1]=='*')

                      a.l=cost;

                    else a.l=0;

                    g[x].push_back(a);

                }

                if(i+1<r&&str[i+1][j]!='#')

                {

                    if(str[i+1][j]=='P'&&p==-1)p=find(i+1,j);

                    if(str[i+1][j]=='P'&&p!=-1)y=p;

                    else y=find(i+1,j);



                    a.k=y;

                    if(str[i+1][j]=='*')

                      a.l=cost;

                    else a.l=0;

                   g[x].push_back(a);

                }

                if(j-1>=0&&str[i][j-1]!='#')

                {

                    if(str[i][j-1]=='P'&&p==-1)p=find(i,j-1);

                    if(str[i][j-1]=='P'&&p!=-1)y=p;

                    else

                        y=find(i,j-1);

                    a.k=y;

                   if(str[i][j-1]=='*')

                    a.l=cost;

                    else a.l=0;

                    g[x].push_back(a);

                }



            }

        }

    }

}

int SPFA()

{



    int i,j,k,min;

    node  a;

    memset(vis,0,sizeof(vis));





    for(i=0;i<=max1;i++)dis[i]=inf;



    dis[s]=0;

    vis[s]=1;

    int head=0,tail=0;

    queue[head]=s;

    tail++;

    while(head!=tail)

    {

        int k=queue[head];

        for(i=0;i<g[k].size();i++)

        {

            node a=g[k][i];

            int b=a.k;

            if(dis[k]+a.l<dis[b])

            {

                dis[b]=dis[k]+a.l;

                if(!vis[b])

                {

                    vis[b]=1;

                    queue[tail]=b;

                    tail++;

                    if(tail==maxn*200)tail=0;

                }

            }

        }

        head++;

        if(head==maxn*200)head=0;

    }

    return dis[e];











}

int main()

{

    int i,j;

    while(scanf("%d%d%d",&r,&c,&cost)!=EOF)

    {



         for(i=0;i<=r*c;i++)g[i].clear();

        max1=-1;

        p=-1;



        for(i=0;i<r;i++)

        {

            scanf("%s",str[i]);

        }

        build();



        int ans=dij();

        if(ans==inf)printf("Damn teoy!\n");

        else printf("%d\n",ans);

    }

}