#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main()
{
  int h, w, a, b;
  cin >> h >> w >> a >> b;
  int r[2], c[2];
  for (int i = 0; i < 2; ++i) cin >> r[i] >> c[i];
  int ans = 1e9;
  int p, q;
  cin >> p >> q;
  for (int i = r[0]; i <= r[1]; ++i)
  {
    for (int j = c[0]; j <= c[1]; ++j)
    {
      int tmp = abs(a - i) + abs(b - j) + abs(i - p) + abs(j - q) + abs(p - a) + abs(q - b);
      ans = min(ans, tmp);
    }
  }
  cout << ans << endl;
}