POJ 2312<优先队列><最短路>

#include <stdio.h>
#include <queue>
#include <cstring>
using namespace std;
char a[305][305];

int n,m;
int sx,sy,ex,ey;
int v[4][2] = {{1,0},{-1,0},{0,1},{0,-1}};
bool f[305][305];
struct node
{
	int x,y,w;
	bool operator < (const node& q) const
	{
		return w > q.w;
	} 
};
int fun()
{
	priority_queue<node> que;
	node g;
	g.x = sx;
	g.y = sy;
	g.w = 0;
	que.push(g);
	f[sx][sy] = true;
	while(!que.empty())
	{
		node tm = que.top();
		que.pop();
		for(int i = 0; i < 4;i++)
		{
			node q;
			q.x = tm.x + v[i][0];
			q.y = tm.y + v[i][1];
			q.w = tm.w;
			if(!f[q.x][q.y])
			switch(a[q.x][q.y])
			{
				case 'S':
				case 'R':
					{
						break;
					}
				case 'B':
					{
						q.w += 2;
						que.push(q);
						f[q.x][q.y] = true;
						break;
					}
				case 'E':
					{
						q.w += 1;
						que.push(q);
						f[q.x][q.y] = true;
						break;
					}
				case 'T':
					{						
						return q.w+1;
					}				
			}
		}
	}
	return -1;
}
int main()
{
	
	while(scanf("%d%d",&n,&m), n||m)
	{
		for(int i = 0; i <= m+1;i++)
		{
			a[0][i] = 'S';
			a[n+1][i] = 'S';
		}
		for(int i = 0 ; i<= n+1;i++)
		{
			a[i][0] = 'S';
			a[i][m+1] = 'S';
		}
		getchar();
		memset(f,0,sizeof(f));
		for(int i = 1; i <= n;i++ )
		{
			for(int j = 1; j <= m;j++)
			{
				a[i][j] = getchar();
				if(a[i][j] == 'Y')
				{
					sx = i;
					sy = j;
				}
				
			}
			getchar();
		}
		printf("%d\n",fun());
		
	}
	return 0;
}