Language: C++

#include <bits/stdc++.h>
using namespace std;
#define int ll
typedef long long ll ;
const int MAX=1e3+10;
const int INF=0x3f3f3f3f;
const int mod=1e9+7;
int dir[16][2]={{2,0},{0,2},{-2,0},{0,-2},{2,2},{-2,2},{2,-2},{-2,-2},
        {1,2},{1,-2},{-1,2},{-1,-2},{2,1},{2,-1},{-2,1},{-2,-1}};
int dir1[4][2]={{1,0},{-1,0},{0,1},{0,-1}};

struct Node{
    int a,b;
    int ci;

    Node(int aa,int bb,int cc){
        a=aa;
        b=bb;
        ci=cc;
    }
    bool operator>(const Node &no)const {
        return ci<no.ci;
    }
};

char a[MAX][MAX];
bool biao[MAX][MAX];
int h,w;
bool check(int x,int y){
    if(x>=1&&x<=h&&y>=1&&y<=w){
        return true;
    }
    return false;
}

void solve(){
    cin>>h>>w;
    int ch,cw,dh,dw;
    cin>>ch>>cw>>dh>>dw;
    for(int i=1;i<=h;i++){
        for(int j=1;j<=w;j++){
            cin>>a[i][j];
        }
    }
    priority_queue<Node>q;
    priority_queue<Node>q2;
    q.push(Node(ch,cw,0));
    biao[ch][cw]=1;
    bool is=true;
    ll ans=-1;
    while(is&&(!q.empty()||!q2.empty())) {
        while (!q.empty()) {
            Node begin = q.top();
            q.pop();
            if (begin.a == dh && begin.b == dw) {
                ans = begin.ci;
                is = false;
                break;
            }
            for (int i = 0; i < 4; i++) {
                Node next = Node(begin.a + dir1[i][0], begin.b + dir1[i][1], begin.ci);
                if (a[next.a][next.b] == '#') {
                    q2.push(begin);
                }
                if (check(next.a, next.b) && biao[next.a][next.b] == 0 && a[next.a][next.b] == '.') {
                    biao[next.a][next.b] = 1;
                    q.push(next);
                }
            }
        }
        while (!q2.empty()) {
            Node begin = q2.top();
            q2.pop();
            if (begin.a == dh && begin.b == dw) {
                ans = begin.ci;
                is = false;
                break;
            }
            for (int j = 0; j < 16; j++) {
                Node next2 = Node(begin.a + dir[j][0], begin.b + dir[j][1], begin.ci + 1);
                if (check(next2.a, next2.b) && biao[next2.a][next2.b] == 0 && a[next2.a][next2.b] == '.') {
                    biao[next2.a][next2.b] = 1;
                    q.push(next2);
                }
            }
        }
    }
    if(is){
        cout<<-1;
    }else{
        cout<<ans;
    }

}

signed main() {
    //ios::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
    int _=1;
    //cin>>_;
    while(_--){
        solve();
    }
    return 0;
}

Compiler output:
In file included from /usr/include/c++/14/string:49,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_function.h: In instantiation of 'constexpr bool std::less<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = Node]':
/usr/include/c++/14/bits/predefined_ops.h:196:23:   required from 'bool __gnu_cxx::__ops::_Iter_comp_val<_Compare>::operator()(_Iterator, _Value&) [with _Iterator = __gnu_cxx::__normal_iterator<Node*, std::vector<Node, std::allocator<Node> > >; _Value = Node; _Compare = std::less<Node>]'
  196 |         { return bool(_M_comp(*__it, __val)); }
      |                       ~~~~~~~^~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_heap.h:140:48:   required from 'void std::__push_heap(_RandomAccessIterator, _Distance, _Distance, _Tp, _Compare&) [with _RandomAccessIterator = __gnu_cxx::__normal_iterator<Node*, vector<Node, allocator<Node> > >; _Distance = long int; _Tp = Node; _Compare = __gnu_cxx::__ops::_Iter_comp_val<less<Node> >]'
  140 |       while (__holeIndex > __topIndex && __comp(__first + __parent, __value))
      |                                          ~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_heap.h:216:23:   required from 'void std::push_heap(_RAIter, _RAIter, _Compare) [with _RAIter = __gnu_cxx::__normal_iterator<Node*, vector<Node, allocator<Node> > >; _Compare = less<Node>]'
  216 |       std::__push_heap(__first, _DistanceType((__last - __first) - 1),
      |       ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  217 |                        _DistanceType(0), _GLIBCXX_MOVE(__value), __cmp);
      |                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_queue.h:747:16:   required from 'void std::priority_queue<_Tp, _Sequence, _Compare>::push(value_type&&) [with _Tp = Node; _Sequence = std::vector<Node, std::allocator<Node> >; _Compare = std::less<Node>; value_type = Node]'
  747 |         std::push_heap(c.begin(), c.end(), comp);
      |         ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
a.cc:47:11:   required from here
   47 |     q.push(Node(ch,cw,0));
      |     ~~~~~~^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_function.h:405:20: error: no match for 'operator<' (operand types are 'const Node' and 'const Node')
  405 |       { return __x < __y; }
      |                ~~~~^~~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_pair.h:1045:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator<(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1045 |     operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1045:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_function.h:405:20: note:   'const Node' is not derived from 'const std::pair<_T1, _T2>'
  405 |       { return __x < __y; }
      |                ~~~~^~~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:448:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  448 |     operator<(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:448:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_function.h:405:20: note:   'const Node' is not derived from 'const std::reverse_iterator<_Iterator>'
  405 |       { return __x < __y; }
      |                ~~~~^~~~~
/usr/include/c++/14/bits/stl_iterator.h:493:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  493 |     operator<(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:493:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_function.h:405:20: note:   'const Node' is not derived from 'const std::reverse_iterator<_Iterator>'
  405 |       { return __x < __y; }
      |                ~~~~^~~~~
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1694 |     operator<(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_function.h:405:20: note:   'const Node' is not derived from 'const std::move_iterator<_IteratorL>'
  405 |       { return __x < __y; }
      |                ~~~~^~~~~
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1760 |     operator<(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_function.h:405:20: note:   'const Node' is not derived from 'const std::move_iterator<_IteratorL>'
  405 |       { return __x < __y; }
      |                ~~~~^~~~~