#include <stdio.h>
int x, y, minstep, step = 0;
int book[101][101] = {3};
int n, m;
int stx, sty, enx, eny;

int check(int x,int y)
{
	
	if(book[x][y] == 0 &&x >= 0 && x <= n && y >= 0 && y <= m)
	 {
	 	return 1;
	 }
	 return 0;
}

int dfs(int x,int y)
{
	int next[4][2] = {{1,0},{0,1},{-1,0},{0,-1}};
	if(stx == enx && sty == eny)
	{
		if(step < minstep)
		{
			minstep = step;
		}
		return minstep;
	}
	if(check(x,y))
	{
		step ++; 
		int xx, yy;
		for(int k = 0; k <= 3; k ++) 
		{
			xx = x + next[k][0];
			yy = y + next[k][1];
			book[xx][yy] == 1;
			dfs(xx,yy);
			book[xx][yy] == 0;
		}
	}
}
	
int main()
{
	 scanf("%d %d",&n ,&m); 
	 char map[n][m];
	 for(int i = 0 ; i < n ;i ++)
	 {
	 	scanf("%s",map[i]);
	 }
	 for(int i = 0 ; i < n; i ++)
	 {
	 	for(int j = 0; j < m; j ++)
		 {
		 	if(map[i][j] == '1')
			{
				book[i][j] == 1;
			}
		}
	 }
	 scanf("%d %d %d %d",&stx, &sty ,&enx, &eny);
	 dfs( stx , sty);
	 printf("%d",minstep);
}