Saving Princess claire_&&http://acm.hdu.edu.cn/showproblem.php?pid=4308

BFS入门题。。

AC代码：

#include<iostream>
#include<cstdio>
#include<string.h>
#include<string>
#include<queue>
#include<set> Q;
#define N 5005
using namespace std;
typedef struct node
{
	int x;
	int y;
	int step;
	bool flag;
	bool operator<(const node& a)
	{return a.step<step;}
}Node;
char map[N][N];
Node now,last,cur;
int endx,endy;
int n,m,cost;
int dx[]={0,0,1,-1};
int dy[]={1,-1,0,0};
queue<Node>Q;
int bfs()
{
	queue<Node>Q1;
	now.step=0;
	now.flag=0;
	Q1.push(now);
	map[now.x][now.y]='#';
	while(!Q1.empty())
	{
		cur=Q1.front();
		Q1.pop();
		int sa=cur.x;
		int sb=cur.y;
		int step=cur.step;
		int flag=cur.flag;
		if(flag)
		{
			while(!Q.empty())
			{
				now=Q.front();
				 Q.pop();
				  int a=now.x;
				  int b=now.y;
				  if(map[a][b]!='#') 
					{
					  now.x=a,now.y=b,now.step=step,now.flag=1,Q1.push(now);
				      map[a][b]='#';
				    }
			}
		}
		for(int i=0;i!=4;++i)
		{
			int xx=sa+dx[i];
			int yy=sb+dy[i];
			if(xx==endx&&yy==endy) return step;
			if(xx>=0&&xx<n&&yy>=0&&yy<m&&map[xx][yy]!='#')
			{
				now.x=xx,now.y=yy;
				if(map[xx][yy]=='*') {now.step=step+cost,now.flag=0;}
				else if(map[xx][yy]=='P'){now.step=step;now.flag=1;}
				Q1.push(now),map[xx][yy]='#';
			}
		}

	}return -1;
}
int main()
{ 
	while(cin>>n>>m>>cost)
   {    
        memset(map,'0',sizeof(map));
        for(int i=0;i<n;i++)
        {  cin>>map[i];
          for(int j=0;j<m;j++)
           {
                  if(map[i][j]=='Y'){now.x=i;now.y=j;}
				  else if(map[i][j]=='C') {endx=i;endy=j;} 
				  else if(map[i][j]=='P') {last.x=i,last.y=j;Q.push(last);}
           }
         }
		int ans=bfs();
		if(ans==-1) cout<<"Damn teoy!"<<endl;
		else cout<<ans<<endl;
         
   }return 0;
}