都不要用万能头了，用这个！！！！！！！！

#include <cctype>
#include <cerrno>
#include <cfloat>
#include <ciso646>
#include <climits>
#include <clocale>
#include <cmath>
#include <csetjmp>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <ccomplex>
#include <cfenv>
#include <cinttypes>
#include <cstdalign>
#include <cstdbool>
#include <cstdint>
#include <ctgmath>
#include <cwchar>
#include <cwctype>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>
#include <array>
#include <atomic>
#include <chrono>
#include <condition_variable>
#include <forward_list>
#include <future>
#include <initializer_list>
#include <mutex>
#include <random>
#include <ratio>
#include <regex>
#include <scoped_allocator>
#include <system_error>
#include <thread>
#include <tuple>
#include <typeindex>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <bits/cconfig.h>
#include <bits/stringfwd.h>
#include <bits/char_traits.h>
#include <bits/allocator.h>
#include <bits/cpp_type_traits.h>
#include <bits/localefwd.h>
#include <bits/ostream_insert.h>
#include <bits/stl_iterator_base_types.h>
#include <bits/stl_iterator_base_funcs.h>
#include <bits/stl_iterator.h>
#include <bits/stl_function.h>
#include <ext/numeric_traits.h>
#include <bits/stl_algobase.h>
#include <bits/range_access.h>
#include <bits/basic_string.h>
#include <bits/basic_string.tcc>
#include <bits/cconfig.h>
#include <ostream>
#include <istream>
#include <bits/stl_tree.h>
#include <bits/stl_set.h>
#include <bits/stl_multiset.h>
#include <bits/range_access.h>
#include <float.h>
#include <crtdefs.h>

using namespace std;

using ll = long long;
const ll N = 1e6 + 10;

ll r, c, x_1, y_1, x_2, y_2;
bool flag = 0;
char mp[N][N];
ll vis[N][N];
ll dx[] = {0, 0, 1, -1};
ll dy[] = {1, -1, 0, 0};

struct node{
ll x, y;
};

void dfs(ll x, ll y){
queue<node> qu;
qu.push({x, y});

if(x == x_2 && y == y_2){
	flag = 1;
	return ;
}
for(ll i = 0; i < 4; i ++){
	ll tx = x + dx[i];
	ll ty = y + dy[i];
	
	if(tx >= 1 && tx <= r && ty >= 1 && ty <= c && mp[tx][ty] != '#' && vis[tx][ty] == 0){
		vis[tx][ty] = 1;
		dfs(tx, ty);
        vis[tx][ty] = 0;
	}else{
        continue;
    }
}

}

int main(){
cin >> r >> c >> x_1 >> y_1 >> x_2 >> y_2;y_2;y_2;
for(ll i = 1; i <= r; i ++){
for(ll j = 1; j <= c; j ++){
cin >> mp[i][j];
}
}

dfs(x_1, y_1);
if(flag) cout << "YES";
else cout << "NO";
return 0;

}

都不要用万能头了，用这个↑