POJ 2251 Dungeon Master

这道题本来不难，但是写的纠结。三维广搜，只有六个方向，有一段时间没写结构体，发现很不熟练。

/*Accepted    612K    16MS    C++    2362B    2012-07-23 17:48:55*/

#include<cstdio>

#include<cstring>

#include<cstdlib>

#include<queue>

using namespace std;



const int MAXN = 50;

const int dx[] = { 1, -1, 0, 0, 0, 0};

const int dy[] = { 0, 0, 1, -1, 0, 0};

const int dz[] = { 0, 0, 0, 0, 1, -1};

int H, R, C;



struct Node

{

    int x, y, z;

    int steps;

};



Node S, E;



char a[MAXN][MAXN][MAXN];

int map[MAXN][MAXN][MAXN];



bool judge( int x, int max)

{

    if( x > 0 && x <= max)

        return true;

    return false;

}



void init()

{

    int i, j, k;

    for( k = 1; k <= H; k ++)

    {

        for( i = 1; i <= R; i ++)

        {

            scanf( "%s", a[k][i] + 1);

            for( j = 1; j <= C; j ++)

            {

                if( a[k][i][j] == '#')

                    map[k][i][j] = 0;

                else  map[k][i][j] = 1;

                if( a[k][i][j] == 'S')

                {

                    S.z = k;

                    S.x = i;

                    S.y = j;

                }

                if( a[k][i][j] == 'E')

                {

                    E.z = k;

                    E.x = i;

                    E.y = j;

                    E.steps = -1;

                }

            }

        }

    }

}



void bfs()

{

    int i;

    Node p1, p2;

    queue<Node> q;

    S.steps = 0;

    q.push(S);

    while( !q.empty())

    {

        p1 = q.front(); q.pop();

        if( p1.z == E.z && p1.x == E.x && p1.y == E.y) break;

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

        {

            p2.x = p1.x + dx[i];

            p2.y = p1.y + dy[i];

            p2.z = p1.z + dz[i];

            if( map[p2.z][p2.x][p2.y] == 1 && judge(p2.z, H) && judge(p2.x, R) && judge(p2.y, C))

            {

                map[p2.z][p2.x][p2.y] = 0;

                p2.steps = p1.steps + 1;

                q.push(p2);

                if( p2.z == E.z && p2.x == E.x && p2.y == E.y){

                    E.steps = p2.steps;

                    return;

                }

            }

        }

    }

}



int main()

{

    while( scanf( "%d%d%d", &H, &R, &C) != EOF)

    {



        if( H == 0 && R == 0 && C == 0) break;

        init();

        bfs();

        if( E.steps < 0)

        {

            printf( "Trapped!\n");

        }

        else

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

    }

    return 0;

}