#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
  ll top = 201,bottom = -1,left = 201,right = -1,h,w,a,b,p,q;
  cin >> h >> w >> a >> b;
  vector<pair<ll,ll>> bug(2);
  for(int i = 0;i < 2;i++){
    int tmp1,tmp2;
    cin >> tmp1 >> tmp2;
    bug.at(i) = make_pair(tmp1,tmp2);
  }
  cin >> p >> q;
  ll ans = 10000000000;
  for(int i = bug.at(0).first;i <= bug.at(1).first;i++){
    for(int j = bug.at(0).second;j <= bug.at(1).second;j++){
      ll s = abs(a - p) + abs(b - q);
      s += abs(p - i) + abs(q - j);
      s += abs(a - i) + abs(b - j);
      ans = min(ans,s);
    }
  }
  cout << ans << endl;
}