#include <iostream>
#include <queue>
using namespace std;
  
int N, M, Hx, Hy, Ex, Ey;
bool map[1002][1002];
bool visited[1002][1002][2];
queue<int*> q;
  
void pushQueue(int i, int j, int c, int m){
	if(!visited[i][j][m]){
		if(map[i][j] == 0){
			q.push(new int[4]{i, j, c, m});
		}
		else if(m == 0){
			q.push(new int[4]{i, j, c, 1});
		}
		visited[i][j][m] = visited[i][j][1] = true;
	}
}
  
int BFS(){
	q.push(new int[4]{Hx, Hy, 0, 0});
	visited[Hx][Hy][0] = visited[Hx][Hy][1] = true;
	do{
		int* temp = q.front();
		q.pop();
		int i = temp[0];
		int j = temp[1];
		int c = temp[2];
		int m = temp[3];
		if(i == Ex && j == Ey) return c;
  		
		pushQueue(i+1, j, c+1, m);
		pushQueue(i-1, j, c+1, m);
		pushQueue(i, j+1, c+1, m);
		pushQueue(i, j-1, c+1, m);
	}while(!q.empty());
	return -1;
}
  
int main()
{
	cin >> N >> M >> Hx >> Hy >> Ex >> Ey;
	for(int i = 0; i <= N+1; i++){
        visited[i][0][0] = visited[i][M+1][0] = visited[i][0][1] = visited[i][M+1][1] = true;
    }
	for(int j = 0; j <= M+1; j++){
        visited[0][j][0] = visited[N+1][j][0] = visited[0][j][1] = visited[N+1][j][1] = true;
    }
	for(int i = 1; i <= N; i++){
		for(int j = 1; j <= M; j++){
			cin >> map[i][j];
		}
	}
	cout << BFS();
}