#include <iostream>

char maze[1005][1005];
int x1,y1,x2,y2;

bool flag[1005][1005];

int q[4][1005000];

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

int n;

void bfs(int x,int y)
{
	int h = 1 ,r = 2;
	q[1][h] = x;
	q[2][h] = y;
	q[3][h] = 0;
	flag[x][y] = true;
	while (h < r)
	{
		for (int i = 0 ; i < 4 ; i ++)
		{
			int xx = q[1][h] + dx[i];
			int yy = q[2][h] + dy[i];
			if (xx > 0 && yy > 0 && xx <= n && yy <= n && maze[xx][yy] == '0' && flag[xx][yy] == false)
			{
				flag[xx][yy] == true;
				q[1][r] = xx;
				q[2][r] = yy;
				q[3][r] = q[3][h] + 1;
				if (xx == x2 && yy == y2)
				{
					std :: cout << q[3][r];
					return;
				}
				r ++;
			}
		}
		h ++;
	}
}

int main()
{
	std :: cin >> n;
	for (int i = 1 ; i <= n ; i ++)
	{
		for (int j = 1 ; j <= n ; j ++)
		{
			std :: cin >> maze[i][j];
		}
	}
	std :: cin >> x1 >> y1 >> x2 >> y2;
	bfs(x1,y1);
}

样例过了，但只有10分