POJ-2251 Dungeon Master bfs搜索

就是将普通的二维推广到三维，方向变成了六个。

代码如下：

#include <cstring>

#include <cstdio>

#include <cstdlib>

using namespace std;



int L, N, M, sx, sy, sz;

 

struct Node

{

    int x, y, z, t;    

}e[100005], pos;



int front, tail, dir[6][3] ={

    0, 1, 0,

    0, -1, 0,

    1, 0, 0,

    -1, 0, 0,

    0, 0, 1, 

    0, 0, -1

};  // 六个方向，三个坐标 



char G[35][35][35];



bool judge(int x, int y, int z)

{

    if (x < 1 || x > N || y < 1 || y > M || z < 1 || z > L) {

        return false;

    }    

    else {

        return true;

    }

}



int bfs()

{

    int xx, yy, zz;

    front = 0;

    tail = 1;

    e[tail].x = sx, e[tail].y = sy;

    e[tail].z = sz,e[tail].t = 0;

    while (front != tail) {

        pos = e[++front];

        for (int i = 0; i < 6; ++i) {

            xx = pos.x + dir[i][0];

            yy = pos.y + dir[i][1];

            zz = pos.z + dir[i][2];

            if (judge(xx, yy, zz)) {

                if (G[zz][xx][yy] == '.') {

                    ++tail;

                    e[tail].x = xx, e[tail].y = yy;

                    e[tail].z = zz, e[tail].t = pos.t + 1;        

                    G[zz][xx][yy] = '#';

                }

                else if (G[zz][xx][yy] == 'E') {

                    return pos.t + 1;

                }

            }

        }

    }

    return -1;

}



int main()

{

    int flag, ans;

    while (scanf("%d %d %d", &L, &N, &M), L|N|M) {

        flag = 0;

        for (int i = 1; i <= L; ++i) {

            for (int j = 1; j <= N; ++j) {

                scanf("%s", G[i][j]+1);

                for (int k = 1; k <= M && !flag; ++k) {

                    if (G[i][j][k] == 'S') {

                        sx = j, sy = k, sz = i;

                        G[i][j][k] = '#';

                        flag = 1;

                        break;

                    }

                }

            }

        }

        ans = bfs();

        if (ans == -1) {

            printf("Trapped!\n");

        }

        else {

            printf("Escaped in %d minute(s).\n", ans);

        }

    }

    return 0;        

}