POJ 2251 Dungeon Master (bfs)

//三维迷宫
//标准的bfs
#include <iostream>
#include <queue>
#include <memory.h>
using namespace std;

struct coordinate
{
	int x,y,z,step;
};

int L,R,C;
bool isvisited[31][31][31];
bool place[31][31][31];
coordinate goal;
coordinate start;
int times;
void bfs();
int dir[6][3] = {{0, 0, 1}, {0, 0, -1}, {1, 0, 0}, {-1, 0, 0}, {0, 1, 0}, {0, -1, 0}};

int main()
{
	char c;
	while (cin >> L >> R >> C && (L || R || C))
	{
		memset(place, true, sizeof(place));
		for (int i = 1; i <= L; i++) //z
		{
			for (int j = 1; j <= R; j++)//x
			{
				for (int k = 1; k <= C; k++)//y
				{
					cin >> c;
					if (c == 'E')
					{
						goal.x = j;
						goal.y = k;
						goal.z = i;
					}
					else if (c == 'S')
					{
						start.x = j;
						start.y = k;
						start.z = i;
					}
					else if (c == '#')
						place[j][k][i] = false;
				}
			}
		}

		bfs();
		
	}
	return 0;
}

void bfs()
{
	memset(isvisited, false, sizeof(isvisited));
	queue<coordinate> Q;
	coordinate p, tmp;
	start.step = 0;
	Q.push(start);
	isvisited[start.x][start.y][start.z] = true;

	while (!Q.empty())
	{
		tmp = Q.front();
		Q.pop();

		if (tmp.x == goal.x && tmp.y == goal.y && tmp.z == goal.z)
		{
			cout << "Escaped in " << tmp.step << " minute(s)." << endl;
			return ;
		}

		for (int i = 0; i < 6; i++)
		{
			p.x = tmp.x + dir[i][0];
			p.y = tmp.y + dir[i][1];
			p.z = tmp.z + dir[i][2];
			p.step = tmp.step + 1;

			if (p.x > 0 && p.x <= R && p.y > 0 && p.y <= C && p.z > 0 && p.z <= L
			   && place[p.x][p.y][p.z]
			   && !isvisited[p.x][p.y][p.z])
			   {
				   isvisited[p.x][p.y][p.z] = true; 
				   Q.push(p);
			   }
		}		
	}
	cout << "Trapped!" << endl;
}