#include <bits/stdc++.h>
using namespace std;
void itval(istream_iterator<string> it) {}
template <typename T, typename... Args>
void itval(istream_iterator<string> it, T a, Args... args) {
  cerr << *it << " = " << a << endl;
  itval(++it, args...);
}
const long long int MOD = 1e9 + 9;
template <typename T>
inline void print(T x) {
  cout << x << "\n";
}
template <typename T>
inline void printvec(T x) {
  for (auto a : x) cout << a << ' ';
  cout << '\n';
}
struct custom {
  bool operator()(
      const pair<long long int, pair<long long int, long long int> > &p1,
      const pair<long long int, pair<long long int, long long int> > &p2)
      const {
    if (p1.first == p2.first) {
      if (p1.second.first == p2.second.first)
        return p1.second.second < p2.second.second;
      return p1.second.first < p2.second.first;
    }
    return p1.first < p2.first;
  }
};
long long int get_pow(long long int a, long long int b) {
  long long int res = 1;
  while (b) {
    if (b & 1) res = (res * a) % MOD;
    a = (a * a) % MOD;
    b >>= 1;
  }
  return res;
}
const long long int N = 2e3 + 10, inf = 4e18;
char a[N][N];
int d[N][N];
int n, m, dx[4] = {1, -1, 0, 0}, dy[4] = {0, 0, 1, -1}, sx, sy, lx, rx;
int ans = 0;
inline bool check(int i, int z) { return i >= 0 && i < z; }
set<pair<long long int, pair<long long int, long long int> >, custom> s;
void solve() {
  cin >> n >> m;
  cin >> sx >> sy >> lx >> rx;
  for (long long int i = (long long int)0; i < (long long int)(n); i++)
    for (long long int j = (long long int)0; j < (long long int)(m); j++) {
      cin >> a[i][j];
      d[i][j] = INT_MAX;
    }
  sx--;
  sy--;
  d[sx][sy] = 0;
  s.insert({0, {sx, sy}});
  while (!s.empty()) {
    auto p = *s.begin();
    s.erase(s.begin());
    int i = p.second.first, j = p.second.second;
    for (int k = 0; k < 3; ++k) {
      int x = i + dx[k], y = j + dy[k];
      if (check(x, n) && check(y, m) && a[x][y] == '.' && d[x][y] > d[i][j]) {
        auto it = s.find({d[x][y], {x, y}});
        if (it != s.end()) s.erase(it);
        d[x][y] = d[p.second.first][p.second.second];
        s.insert({d[x][y], {x, y}});
      }
    }
    for (int k = 3; k < 4; ++k) {
      int x = i + dx[k], y = j + dy[k];
      if (check(x, n) && check(y, m) && a[x][y] == '.' &&
          d[x][y] > d[i][j] + 1) {
        auto it = s.find({d[x][y], {x, y}});
        if (it != s.end()) s.erase(it);
        d[x][y] = d[i][j] + 1;
        s.insert({d[x][y], {x, y}});
      }
    }
  }
  for (long long int i = (long long int)0; i < (long long int)(n); i++) {
    for (long long int j = (long long int)0; j < (long long int)(m); j++) {
      if (a[i][j] == '.') {
        int l = d[i][j];
        int r = j - sy + l;
        if (l <= lx && r <= rx) ans++;
      }
    }
  }
  cout << ans;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int test = 1;
  clock_t z = clock();
  for (long long int tes = (long long int)0; tes < (long long int)(test);
       tes++) {
    solve();
  }
  fprintf(stderr, "Total Time:%.4f\n", (double)(clock() - z) / CLOCKS_PER_SEC),
      fflush(stderr);
  return 0;
}
