#include <bits/stdc++.h>

int main() {
  std::ios::sync_with_stdio(false);
  std::cin.tie(nullptr);

  int w, h, k, l;
  std::cin >> w >> h >> k >> l;
  int xh, yh, xv, yv;
  std::cin >> xh >> yh >> xv >> yv;
  int sx = xv, sy = yh;
  int ex = -1, ey = -1;
  std::vector block(w, std::vector<bool>(h));
  std::vector<std::vector<int>> loc_r(w, {-1}), loc_c(h, {-1});
  for (int j = 0; j < h; ++j) {
    for (int i = 0; i < w; ++i) {
      char c;
      std::cin >> c;
      block[i][j] = c == 'X';
      if (c == '*') {
        ex = i;
        ey = j;
      }
      if (block[i][j]) {
        loc_r[i].push_back(j);
        loc_c[j].push_back(i);
      }
    }
  }
  for (int i = 0; i < w; ++i) {
    loc_r[i].push_back(h);
  }
  for (int i = 0; i < h; ++i) {
    loc_c[i].push_back(w);
  }
  auto near_r = [&](int x, int y) -> std::pair<int, int> {
    auto it = std::lower_bound(loc_r[x].begin(), loc_r[x].end(), y);
    return {*std::prev(it), *it};
  };
  auto near_c = [&](int x, int y) -> std::pair<int, int> {
    auto it = std::lower_bound(loc_c[y].begin(), loc_c[y].end(), x);
    return {*std::prev(it), *it};
  };
  std::vector vis(w, std::vector<bool>(h));
  auto inter = [&](int l1, int r1, int l2, int r2) {
    return std::max(0, std::min(r1, r2) - std::max(l1, l2) + 1);
  };
  auto dfs = [&](auto &self, int x, int y) -> void {
    if (x == ex && y == ey) {
      std::cout << "YES\n";
      std::exit(0);
    }
    // move row
    for (int d : {-1, 1}) {
      if (x + d < 0 || x + d >= w || vis[x + d][y] || block[x + d][y]) {
        continue;
      }
      auto [cl, cr] = near_r(x, y);
      auto [nl, nr] = near_r(x + d, y);
      int width = inter(cl + 1, cr - 1, nl + 1, nr - 1);
      if (width >= l) {
        vis[x + d][y] = true;
        self(self, x + d, y);
      }
    }
    // move column
    for (int d : {-1, 1}) {
      if (y + d < 0 || y + d >= h || vis[x][y + d] || block[x][y + d]) {
        continue;
      }
      auto [cl, cr] = near_c(x, y);
      auto [nl, nr] = near_c(x, y + d);
      int width = inter(cl + 1, cr - 1, nl + 1, nr - 1);
      if (width >= k) {
        vis[x][y + d] = true;
        self(self, x, y + d);
      }
    }
  };
  vis[sx][sy] = true;
  dfs(dfs, sx, sy);
  std::cout << "NO\n";
}