#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
using namespace std;
using ll = long long;
using ld = long double;
using VI = vector<ll>;
using VV = vector<VI>;
using VS = vector<string>;
using PII = pair<ll, ll>;
template <typename A, typename B>
string to_string(pair<A, B> p);
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
string to_string(const string& s) { return '"' + s + '"'; }
string to_string(const char* s) { return to_string((string)s); }
string to_string(bool b) { return (b ? "true" : "false"); }
string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto& x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ")";
}
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
         to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
void debug_out() { cerr << '\n'; }
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
template <class T>
bool chmax(T& a, const T& b) {
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T& a, const T& b) {
  if (b < a) {
    a = b;
    return 1;
  }
  return 0;
}
ll SUM(VI& V) { return accumulate((V).begin(), (V).end(), 0LL); }
ll MIN(VI& V) { return *min_element((V).begin(), (V).end()); }
ll MAX(VI& V) { return *max_element((V).begin(), (V).end()); }
void print_vector(VI& V) {
  ll n = V.size();
  for (ll i = (0); i < (n); ++i) {
    if (i) cout << ' ';
    cout << V[i];
  }
  cout << endl;
}
ll gcd(ll a, ll b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
ll lcm(ll a, ll b) {
  ll g = gcd(a, b);
  return a / g * b;
}
using ld = long double;
void no() {
  cout << ("NO") << '\n';
  exit(0);
}
void yes() {
  cout << ("YES") << '\n';
  exit(0);
}
const ll mod = 1e9 + 7;
const ll inf = 1e18;
const double PI = acos(-1);
struct mint {
  ll x;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint& operator+=(const mint a) {
    if ((x += a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator-=(const mint a) {
    if ((x += mod - a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
  mint pow(ll t) const {
    if (!t) return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1) a *= *this;
    return a;
  }
  mint inv() const { return pow(mod - 2); }
  mint& operator/=(const mint a) { return (*this) *= a.inv(); }
  mint operator/(const mint a) const {
    mint res(*this);
    return res /= a;
  }
};
int dx[4] = {-1, 0, 1, 0};
int dy[4] = {0, 1, 0, -1};
ll H, W;
bool in_range(ll i, ll j) {
  if (0 <= i && i < H && 0 <= j && j < W) {
    return true;
  } else {
    return false;
  }
}
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin >> H >> W;
  ll r, c;
  cin >> r >> c;
  r--;
  c--;
  ll x, y;
  cin >> x >> y;
  VS S(H);
  for (ll i = (0); i < (H); ++i) cin >> S[i];
  VV G(H, VI(W, inf));
  deque<PII> que;
  que.push_back({r, c});
  G[r][c] = 0;
  while (!que.empty()) {
    auto pa = que.front();
    que.pop_front();
    ll y = pa.first;
    ll x = pa.second;
    ll d = G[y][x];
    for (ll i = (0); i < (4); ++i) {
      ll ny = y + dy[i];
      ll nx = x + dx[i];
      if (!in_range(ny, nx)) continue;
      if (S[ny][nx] == '*') continue;
      ll cost;
      if (i == 0) {
        cost = 1;
      } else {
        cost = 0;
      }
      if (G[ny][nx] <= d + cost) continue;
      G[ny][nx] = d + cost;
      if (cost) {
        que.push_back({ny, nx});
      } else {
        que.push_front({ny, nx});
      }
    }
  }
  ll cnt = 0;
  for (ll i = (0); i < (H); ++i) {
    for (ll j = (0); j < (W); ++j) {
      if (S[i][j] == '*') continue;
      ll l = G[i][j];
      ll diff = j - c;
      ll r = diff + l;
      if (l <= x and r <= y) cnt++;
    }
  }
  cout << (cnt) << '\n';
  return 0;
}
