#include <bits/stdc++.h>
#include <atcoder/modint>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
using ll = long long;
const int INF = 1001001001;
const ll LINF = 3001001001001001001;
const int MOD = 998244353;
const string Yes = "Yes";
const string No = "No";
#define reps(i, a, n) for (ll i = (a); i < (ll)(n); ++i)
#define rep(i, n) reps(i, 0, n)
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
template<typename T> bool chmin(T& a, T b){if(a > b){a = b; return true;} return false;}
template<typename T> bool chmax(T& a, T b){if(a < b){a = b; return true;} return false;}
template<typename T> istream &operator>>(istream &is, vector<T> &v) {for (T &in : v)is >> in;return is;}
vector<pair<int,int>> dir = {{0,1},{0,-1},{1,0},{-1,0},};
// #include <ext/pb_ds/assoc_container.hpp>
// template<typename T>
// using ordered_set = __gnu_pbds::tree<T, null_type, std::less<T>, rb_tree_tag, tree_order_statistics_node_update>;

int main() {
  int h,w;cin>>h>>w;
  int si,sj,gi,gj;cin>>si>>sj>>gi>>gj;
  si--,sj--,gi--,gj--;
  int ans = 0;
  vector ng(h,vector(w,false));
  ng.at(si).at(sj) = true;
  auto in = [&](unsigned x,unsigned y) -> bool {
    return x<h&&y<w;
  };
  auto dfs = [&](auto f,int x,int y) {
    if(x==gi&&y==gj) {
      ans++;
      return;
    }
    vector<pair<int,int>> ns;
    for(auto [dx,dy] : dir) {
      int nx = x+dx;
      int ny = y+dy;
      if(!in(nx,ny)) continue;
      if(ng.at(nx).at(ny)) continue;
      ns.push_back(pair(nx,ny));
      ng.at(nx).at(ny) = true;
    }
    for(auto [nx,ny] : ns) {
      f(f,nx,ny);
    }
    for(auto [nx,ny] : ns) {
      ng.at(nx).at(ny) = false;
    }
  };
  dfs(dfs,si,sj);
  cout << ans << endl;

  return 0;
}