NYOJ 523

NYOJ 523

法一：

#include <stdio.h>
#include <string.h>
#include <queue>
using namespace std;

int map[55][55][55],f[]={1,-1,0,0,0,0},g[]={0,0,1,-1,0,0},w[]={0,0,0,0,1,-1};
bool vis[55][55][55],flag;
struct Node
{
    int x,y,z,step;
};

int bfs(int a,int b,int c,int time)
{
    int i,j,k;
     int r,s,t;
    memset(vis,0,sizeof(vis));
    queue <Node> q;
    Node temp={0,0,0,time};
    vis[0][0][0]=1;
    q.push(temp);
    while(!q.empty())
    {
        temp=q.front();
        q.pop();
        for(i=0;i<6;i++)
        {
            r=temp.x+f[i];
            s=temp.y+g[i];
            t=temp.z+w[i];
            if(r>=0&&r<a&&s>=0&&s<b&&t>=0&&t<c&&vis[r][s][t]==0)
            {
                if(r==a-1&&s==b-1&&t==c-1&&map[r][s][t]==0&&temp.step-1>=0)
                {
                    flag=1;
                    break;
                }
                else if(map[r][s][t]==0&&temp.step-1)
                {
                    Node next={r,s,t,temp.step-1};
                    q.push(next);
                    vis[r][s][t]=1;
                }
            }
        }
        if(flag==1||temp.step-1==0)
            break;
    }
    while(!q.empty())
        q.pop();
    return time-(temp.step-1);
}

int main()
{
    int a,b,c;
     int i,j,k,T;
     int time;
    scanf("%d",&T);
    while(T--)
    {
        memset(map,0,sizeof(map));
        flag=0;
        scanf("%d%d%d%d",&a,&b,&c,&time);
        for(k=0;k<a;k++)
        {
            for(i=0;i<b;i++)
            {
                for(j=0;j<c;j++)
                {
                    scanf("%d",&map[k][i][j]);
                }
            }
        }
        int cnt=bfs(a,b,c,time);
        if(flag==1)
            printf("%d\n",cnt);
        else
            printf("-1\n");
    }
    return 0;
}

法二：

#include<iostream>
#include<cstring>
#include<cstdio>
#include<queue>
#include<algorithm>
using namespace std;

const int N = 55;
const int dir[6][3] = {{0, 0, 1}, {0, 0, -1}, {-1, 0, 0}, {1, 0, 0}, {0, 1, 0}, {0, -1, 0}};

struct node
{
	int x, y, z;
	int ceng;
}que[50000];

int maze[N][N][N];
int a, b, c, t;
int num;
int head, tail;

int Scan()
{
	int res = 0 , ch;
	while( !( ( ch = getchar() ) >= '0' && ch <= '9' ) )
	{
		if( ch == EOF )  return 1 << 30 ;
	}
	res = ch - '0' ;
	while( ( ch = getchar() ) >= '0' && ch <= '9' )
		res = res * 10 + ( ch - '0' ) ;
	return res ;
}

int BFS()
{
	node cur;
	cur.x = 1, cur.y = 1, cur.z = 1, cur.ceng = 0;
	maze[cur.x][cur.y][cur.z] = 0;

	que[tail++] = cur;
	while(head < tail)
	{
		node temp = que[head++];

		if(temp.ceng > t) //无法到达
			return -1;
		if(temp.x == a && temp.y == b && temp.z == c && temp.ceng <= t)
			return temp.ceng;

		for(int i = 0; i < 6; ++i)
		{
			node now;
			now.x = temp.x + dir[i][0]; now.y = temp.y + dir[i][1]; now.z = temp.z + dir[i][2];
			if(maze[now.x][now.y][now.z])
			{
				now.ceng = temp.ceng + 1;
				que[tail++] = now;
				maze[now.x][now.y][now.z] = 0;
			}
		}
	}
	return -1;
}

int main()
{
	int ncase;
	ncase = Scan();
	while(ncase--)
	{
		num = head = tail = 0;
		memset(maze, 0, sizeof(maze));
		a = Scan(), b = Scan(), c = Scan(), t = Scan();
		for(int i = 1; i <= a; ++i)
			for(int j = 1; j <= b; ++j)
				for(int k = 1; k <= c; ++k)
				{
					maze[i][j][k] = Scan() ^ 1;
					num += maze[i][j][k];
				}

		if(maze[a][b][c] == 0 || num < a + b + c - 3) //终点无法走
		{
			printf("-1\n");
			continue;
		}
		printf("%d\n", BFS());
	}
	return 0;
}