Dungeon Master POJ 2251

题目链接： http://poj.org/problem?id=2251

题意：现有一个三维的地牢，问你能否逃出。

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<math.h>
#include<algorithm>
#include<queue>
#include<iostream>
using namespace std;

#define maxn 50
#define INF 0xfffffff
int dir[6][3] = { {1, 0, 0}, {-1, 0, 0}, {0, 0, 1}, {0, 0, -1}, {0, 1, 0}, {0, -1, 0} };
int l, r, c;
char maps[maxn][maxn][maxn];
int v[maxn][maxn][maxn];

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

int BFS(node s, node e)
{
    queue<node>Q;
    s.step = 0;
    Q.push(s);

    while(Q.size())
    {
        node now, next;
        now = Q.front();
        Q.pop();

        if(now.x == e.x && now.y == e.y && now.z == e.z)
            return now.step;

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

            if(next.x>=0 && next.x<l && next.y>=0 && next.y<r && next.z>=0 && next.z<c
               && !v[next.x][next.y][next.z] && maps[next.x][next.y][next.z]!='#')
            {
                v[next.x][next.y][next.z] = 1;
                next.step = now.step + 1;
                Q.push(next);
            }
        }
    }
    return -1;
}
int main()
{
    node s, e;
    while(scanf("%d %d %d", &l, &r, &c), l+r+c)
    {

        memset(v, 0, sizeof(v));
        for(int i=0; i<l; i++)
        {
            for(int j=0; j<r; j++)
            {
                scanf("%s", maps[i][j]);
                for(int k=0; k<c; k++)
                {
                    if(maps[i][j][k] == 'S')
                        s.x=i,s.y=j,s.z=k;
                    if(maps[i][j][k] == 'E')
                        e.x=i,e.y=j,e.z=k;
                }
            }
        }

        int ans = BFS(s,e);

        if(ans == -1)  printf("Trapped!
");
        else printf("Escaped in %d minute(s).
",ans);

    }
    return 0;
}