poj2251

简单题

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;

#define maxn 35

struct Point
{
    int x, y, z;
} s, e;

int dir[6][3] =
{
{ 1, 0, 0 },
{ -1, 0, 0 },
{ 0, 1, 0 },
{ 0, -1, 0 },
{ 0, 0, 1 },
{ 0, 0, -1 } };
bool map[maxn][maxn][maxn];
int dist[maxn][maxn][maxn];
Point q[maxn * maxn * maxn];
int front, rear;
int nx, ny, nz;

void input()
{
    memset(map, 0, sizeof(map));
    getchar();
    for (int i = 0; i < nz; i++)
    {
        for (int j = 0; j < nx; j++)
        {
            for (int k = 0; k < ny; k++)
            {
                char ch = getchar();
                if (ch == '#')
                    map[j][k][i] = false;
                else
                    map[j][k][i] = true;
                if (ch == 'S')
                {
                    s.z = i;
                    s.x = j;
                    s.y = k;
                }
                if (ch == 'E')
                {
                    e.z = i;
                    e.x = j;
                    e.y = k;
                }
            }
            getchar();
        }
        getchar();
    }
}

bool check(int x, int y, int z)
{
    if (x < 0 || y < 0 || z < 0 || x >= nx || y >= ny || z >= nz)
        return false;
    if (dist[x][y][z] != -1)
        return false;
    return map[x][y][z];
}

int bfs()
{
    memset(dist, -1, sizeof(dist));
    front = 0;
    rear = 1;
    q[0] = s;
    dist[s.x][s.y][s.z] = 0;
    while (front != rear)
    {
        Point a = q[front++];
        if (front == maxn * maxn * maxn)
            front = 0;
        for (int i = 0; i < 6; i++)
        {
            int x = dir[i][0] + a.x;
            int y = dir[i][1] + a.y;
            int z = dir[i][2] + a.z;
            if (check(x, y, z))
            {
                q[rear].x = x;
                q[rear].y = y;
                q[rear++].z = z;
                if (rear == maxn * maxn * maxn)
                    rear = 0;
                dist[x][y][z] = dist[a.x][a.y][a.z] + 1;
                if (x == e.x && y == e.y && z == e.z)
                    return dist[x][y][z];
            }
        }
    }
    return -1;
}

int main()
{
//    freopen("t.txt", "r", stdin);
    while (scanf("%d%d%d", &nz, &nx, &ny), nx | ny | nz)
    {
        input();
        int ans = bfs();
        if (ans == -1)
            printf("Trapped!\n");
        else
            printf("Escaped in %d minute(s).\n", ans);
    }
    return 0;
}