#include<bits/stdc++.h>
#define int long long
using namespace std;
int dx[4]={0,1,0,-1},dy[4]={1,0,-1,0};
int dr[4][6]={{1,5,2,0,4,3},{4,1,0,3,5,2},{3,0,2,5,4,1},{2,1,5,3,0,4}};
signed main(){
  int H,W; cin>>H>>W;
  int sx,sy; cin>>sx>>sy; sx--; sy--;
  int gx,gy; cin>>gx>>gy; gx--; gy--;
  vector<string> G(H);
  for(int i=0;i<H;i++)cin>>G[i];
  vector<vector<vector<int>>> dist(H,vector<vector<int>>(W,vector<int>(6,-1)));
  dist[sx][sy][0]=0;
  queue<tuple<int,int,int>> Q; Q.push({sx,sy,0});
  while(!Q.empty()){
    auto[x,y,r]=Q.front(); Q.pop();
    for(int i=0;i<4;i++){
      int X=x+dx[i],Y=y+dy[i],R=dr[i][r];
      if(0<=X && X<H && 0<=Y && Y<W && G[X][Y]=='.' && dist[X][Y][R]==-1){
        dist[X][Y][R]=dist[x][y][r]+1;
        Q.push({X,Y,R});
      }
    }
  }
  cout<<dist[gx][gy][0]<<endl;
}