#ifdef LOCAL
#include ".debug.hpp"
#else
#define debug(...) 42
#endif
#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;
using ordered_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
const int MXN = 3000;
const int DX[] = {1, -1, 0, 0}, DY[] = {0, 0, 1, -1};
int W, H, K, L, pref[MXN][MXN], targetX = 0, targetY = 0, HB[MXN][MXN], BH[MXN][MXN], HU[MXN][MXN], UH[MXN][MXN], VL[MXN][MXN], VR[MXN][MXN], LV[MXN][MXN], RV[MXN][MXN];
char grid[MXN][MXN];
bool vis[MXN][MXN], used[MXN][MXN];
inline int cnt(const int &x1, const int &y1, const int &x2, const int &y2) {
return pref[x2][y2] - pref[x2][y1 - 1] - pref[x1 - 1][y2] + pref[x1 - 1][y1 - 1];
}
array<int, 2> inter_point(const int &xh, const int &yh, const int &xv, const int &yv) {
int xh1 = xh, yh1 = yh + K - 1, xv1 = xv + L - 1, yv1 = yv;
if (yh <= yv && yv <= yh1 && xv <= xh && xh <= xv1)
return {xh, yv};
return {-1, -1};
}
inline bool Inter(const int &xh, const int &yh, const int &xv, const int &yv) {
array<int, 2> point = inter_point(xh, yh, xv, yv);
return point[0] != -1;
}
bool isValid(const int &type, const int &x, const int &y) {
if (x < 1 || y < 1 || x > H || y > W) return false;
int x1, y1;
if (!type) // horizontal line check
x1 = x, y1 = y + K - 1;
else // vertical line check
x1 = x + L - 1, y1 = y;
if (x1 < 1 || y1 < 1 || x1 > H || y1 > W) return false;
return !cnt(x, y, x1, y1);
}
inline bool isfree(const int &x, const int &y) {
return x >= 1 && y >= 1 && x <= H && y <= W && grid[x][y] != 'X';
}
inline bool isOK(const int &xh, const int &yh, const int &xv, const int &yv) {
if (!isValid(0, xh, yh) || !isValid(1, xv, yv)) return false;
return Inter(xh, yh, xv, yv);
}
void dfs(int xh, int yh, int xv, int yv, const int &x, const int &y) {
vis[x][y] = true;
if (x == targetX && y == targetY) {
cout << "YES\n";
exit(0);
}
int oxh = xh, oyh = yh, oxv = xv, oyv = yv;
for (int d = 0; d < 4; d++) {
int tox = x + DX[d], toy = y + DY[d]; xh = oxh, yh = oyh, xv = oxv, yv = oyv;
if (!isfree(tox, toy)) continue;
if (vis[tox][toy]) continue;
if (DX[d] == 1) {
// down -> horizontal line slid down
if (isOK(xh + 1, yh, xv, yv)) dfs(xh + 1, yh, xv, yv, tox, toy);
else {
if (xh == xv + L - 1) {
if (!isValid(1, xv + 1, yv)) continue;
xv++;
}
int yh1 = yh + K - 1, lmost = max(1, yh - (yh1 - yv)), rmost = min(W, yv + K - 1);
// available range [lmost; rmost]
int nyh = HB[xh][yh];
if (nyh > 0)
if (isOK(xh + 1, nyh, xv, yv)) {
dfs(xh + 1, nyh, xv, yv, tox, toy);
continue;
}
nyh = BH[xh][yh];
if (nyh < MXN)
if (isOK(xh + 1, nyh, xv, yv)) {
dfs(xh + 1, nyh, xv, yv, tox, toy);
continue;
}
}
} else if (DX[d] == -1) {
// up -> horizontal line slid up
if (isOK(xh - 1, yh, xv, yv)) dfs(xh - 1, yh, xv, yv, tox, toy);
else {
if (xh == xv) {
if (!isValid(1, xv - 1, yv)) continue;
xv--;
}
// int yh1 = yh + K - 1, lmost = max(1, yh - (yh1 - yv)), rmost = min(W, yv + K - 1);
// available range [lmost; rmost]
int nyh = HU[xh][yh];
if (nyh > 0)
if (isOK(xh - 1, nyh, xv, yv)) {
dfs(xh - 1, nyh, xv, yv, tox, toy);
continue;
}
nyh = UH[xh][yh];
if (nyh < MXN)
if (isOK(xh - 1, nyh, xv, yv)) {
dfs(xh - 1, nyh, xv, yv, tox, toy);
continue;
}
}
} else if (DY[d] == 1) {
// right -> vertical line slid right
if (isOK(xh, yh, xv, yv + 1)) dfs(xh, yh, xv, yv + 1, tox, toy);
else {
if (yv == yh + K - 1) {
if (!isValid(0, xh, yh + 1)) continue;
yh++;
}
int nyv = VR[xv][yv];
if (nyv < MXN)
if (isOK(xh, yh, xv, nyv)) {
dfs(xh, yh, xv, nyv, tox, toy);
continue;
}
nyv = RV[xv][yv];
if (nyv > 0)
if (isOK(xh, yh, xv, nyv)) {
dfs(xh, yh, xv, nyv, tox, toy);
continue;
}
}
} else {
// left -> vertical line slid left
if (isOK(xh, yh, xv, yv - 1)) dfs(xh, yh, xv, yv - 1, tox, toy);
else {
if (yv == yh) {
if (!isValid(0, xh, yh - 1)) continue;
yh--;
}
int nyv = VL[xv][yv];
if (nyv < MXN)
if (isOK(xh, yh, xv, nyv)) {
dfs(xh, yh, xv, nyv, tox, toy);
continue;
}
nyv = LV[xv][yv];
if (nyv > 0)
if (isOK(xh, yh, xv, nyv)) {
dfs(xh, yh, xv, nyv, tox, toy);
continue;
}
}
}
}
}
signed main() {
#ifndef VOID
cin.tie(nullptr)->sync_with_stdio(false);
#endif
int XH, YH, XV, YV;
cin >> W >> H >> K >> L >> XH >> YH >> XV >> YV, XH++, YH++, XV++, YV++;
swap(XH, YH), swap(XV, YV);
for (int i = 1; i <= H; i++)
for (int j = 1; j <= W; j++) {
cin >> grid[i][j];
if (!targetX && grid[i][j] == '*') targetX = i;
if (!targetY && grid[i][j] == '*') targetY = j;
}
for (int i = 1; i <= H; i++)
for (int j = 1; j <= W; j++)
pref[i][j] = pref[i - 1][j] + pref[i][j - 1] - pref[i - 1][j - 1] + (grid[i][j] == 'X');
memset(HB, 0, sizeof(HB)), memset(BH, 0x3f, sizeof(BH));
memset(HU, 0, sizeof(HU)), memset(UH, 0x3f, sizeof(UH));
for (int i = 1; i <= H; i++) {
for (int j = 1; j + K - 1 <= W; j++) {
if (isValid(0, i + 1, j)) HB[i][j] = j;
HB[i][j] = max(HB[i][j], HB[i][j - 1]);
if (isValid(0, i - 1, j)) HU[i][j] = j;
HU[i][j] = max(HU[i][j], HU[i][j - 1]);
}
for (int j = W - K + 1; j >= 1; j--) {
if (isValid(0, i + 1, j)) BH[i][j] = j;
BH[i][j] = min(BH[i][j], BH[i][j + 1]);
if (isValid(0, i - 1, j)) UH[i][j] = j;
UH[i][j] = min(UH[i][j], UH[i][j + 1]);
}
}
memset(VL, 0x3f, sizeof(VL)), memset(VR, 0x3f, sizeof(VR));
memset(LV, 0, sizeof(LV)), memset(RV, 0, sizeof(RV));
for (int j = 1; j <= W; j++) {
for (int i = H - L + 1; i >= 1; i--) {
if (isValid(1, i, j + 1)) VR[i][j] = i;
VR[i][j] = min(VR[i][j], VR[i + 1][j]);
if (isValid(1, i, j - 1)) VL[i][j] = i;
VL[i][j] = min(VL[i][j], VL[i + 1][j]);
}
for (int i = 1; i + L - 1 <= H; i++) {
if (isValid(1, i, j + 1)) RV[i][j] = i;
RV[i][j] = max(RV[i][j], RV[i - 1][j]);
if (isValid(1, i, j - 1)) LV[i][j] = i;
LV[i][j] = max(LV[i][j], LV[i - 1][j]);
}
}
array<int, 2> inter = inter_point(XH, YH, XV, YV);
dfs(XH, YH, XV, YV, inter[0], inter[1]);
cout << "NO\n";
return 0;
}
