//author:luckYrat(twitter:@luckYrat_)

#include <iostream>

#include <cmath>
#include <algorithm>
#include <iomanip>

#include <string>
#include <vector>
#include <set>
#include <stack>
#include <queue>
#include <map>
#include <bitset>

#include <cctype>
#include <utility>
#include <climits>


using namespace std;
using ll = long long;
using P = pair<ll,ll>;


const int mod = 1000000007;
const int inf = (1<<30)-1;
const ll linf = (1LL<<62LL)-1;
const double EPS = (1e-10);


#define anyfill(n,s) setw(n) << setfill(s)
#define loop(s) for(int i = 0; s > i; i++)
#define rep(i,q) for(int i = 0; (q) > i; i++)
#define repp(i,n,q) for(int i = n; (q) > i; i++)
#define dep(i,q) for(int i = (q); 0 < i; i--)


#define pb push_back
#define fir first
#define scn second
#define ednl endl


#define YesNo(a) (a?"Yes":"No")
#define YESNO(a) (a?"YES":"NO")
#define yesno(a) (a?"yes":"no")

P ar4[4] = {{0,1},{0,-1},{1,0},{-1,0}};
P ar8[8] = {{-1,-1},{-1,0},{-1,1},{0,-1},{0,1},{1,-1},{1,0},{1,1}};

char mp[1000][1000];
struct z{
  int x,y,p;
};
__attribute__((constructor))
void initial() {
 cin.tie(0);
 ios::sync_with_stdio(false);
}
int main(){
  int x,y;cin>>x>>y;
  int sy,sx,gy,gx;cin>>sy>>sx>>gy>>gx;
  for(int i = 0; x > i; i++){
    for(int j = 0; y > j; j++){
      cin>>mp[i][j];
    }
  }
  cout << abs(gy-sy)+abs(gx-sx) << endl;


}