Language: C++

#include<bits/stdc++.h>
#define ll long long
#define ld long double
#define fs first
#define sc second
#define task "tst"
using namespace std;
const ll N = 1e6 + 1;
const ll inf = 1e9 + 7;
typedef pair<ll,ll> LL;
char a[N];
ll h,w,k,n,d[N],x1,x2,y1,y2;
ll scr,dest;
ll trans(ll x,ll y){
    return (x - 1)*w + y;
}
bool chk(ll n){
    return (n > 0&&n <= h*w&&a[n] != '@');
}
void BFS(ll scr){
    queue<ll> q;
    fill(d,d + N + 1,inf);
    d[scr] = 0;
    q.push(scr);
    while(!q.empty()){
        ll t = q.front(); q.pop();
        ll p = ceil((ld) t/w);
        for (ll i = t;i <= t + k;i++){
            if (chk(i)&&i <= p*w){
                if (d[i] > d[t] + 1){
                    d[i] = d[t] + 1;
                    q.push(i);
                }
            }
            else break;
        }
        for (ll i = t;i >= t - k;i--){
            if (chk(i)&&i > (p - 1)*w){
                if (d[i] > d[t] + 1){
                    d[i] = d[t] + 1;
                    q.push(i);
                }
            }
            else break;
        }
        for (ll i = 1;i <= k;i++){
            if (chk(t + i*w)){
                if (d[t + i*w] > d[t] + 1){
                    d[t + i*w] = d[t] + 1;
                    q.push(t + i*w);
                }
            }
            else break;
        }
        for (ll i = 1;i <= k;i++){
            if (chk(t - i*w)){
                if (d[t - i*w] > d[t] + 1){
                    d[t - i*w] = d[t] + 1;
                    q.push(t - i*w);
                }
            }
            else break;
        }
    }
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    if (fopen(task".inp", "r")){
        freopen(task".inp", "r", stdin);
        //freopen(task".out", "w", stdout);
    }
    cin>>h>>w>>k;
    cin>>x1>>y1>>x2>>y2;
    for (ll i = 1;i <= h*w;i++) cin>>a[i];
    scr = trans(x1,y1); dest = trans(x2,y2);

    BFS(scr);
    //cout<<trans(3,4);
    if (d[dest] != inf) cout<<d[dest];
    else cout<<-1;
}


Compiler output:
a.cc:12:23: error: 'long long int y1' redeclared as different kind of entity
   12 | ll h,w,k,n,d[N],x1,x2,y1,y2;
      |                       ^~
In file included from /usr/include/features.h:523,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/os_defines.h:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/c++config.h:683,
                 from /usr/include/c++/14/cassert:43,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:33,
                 from a.cc:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:257:1: note: previous declaration 'double y1(double)'
  257 | __MATHCALL (y1,, (_Mdouble_));
      | ^~~~~~~~~~
a.cc: In function 'int main()':
a.cc:74:12: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   74 |     cin>>x1>>y1>>x2>>y2;
      |     ~~~~~~~^~~~
      |        |     |
      |        |     double(double) noexcept
      |        std::basic_istream<char>::__istream_type {aka std::basic_istream<char>}
In file included from /usr/include/c++/14/sstream:40,
                 from /usr/include/c++/14/complex:45,
                 from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127:
/usr/include/c++/14/istream:170:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(bool&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  170 |       operator>>(bool& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:170:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
/usr/include/c++/14/istream:174:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  174 |       operator>>(short& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:174:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(short int)y1' to 'short int&'
/usr/include/c++/14/istream:177:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(short unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  177 |       operator>>(unsigned short& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:177:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(short unsigned int)y1' to 'short unsigned int&'
/usr/include/c++/14/istream:181:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  181 |       operator>>(int& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:181:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(int)y1' to 'int&'
/usr/include/c++/14/istream:184:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  184 |       operator>>(unsigned int& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:184:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(unsigned int)y1' to 'unsigned int&'
/usr/include/c++/14/istream:188:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  188 |       operator>>(long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:188:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(long int)y1' to 'long int&'
/usr/include/c++/14/istream:192:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  192 |       operator>>(unsigned long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:192:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(long unsigned int)y1' to 'long unsigned int&'
/usr/include/c++/14/istream:199:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  199 |       operator>>(long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:199:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(long long int)y1' to 'long long int&'
/usr/include/c++/14/istream:203:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  203 |       operator>>(unsigned long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:203:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(long long unsigned int)y1' to 'long long unsigned int&'
/usr/include/c++/14/istream:328:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(void*&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  328 |       operator>>(void*& __p)
      |       ^~~~~~~~
/usr/include/c++/14/istream:328:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
a.cc:74:14: error: cannot bind rvalue '(void*)y1' to 'void*&'
/usr/include/c++/14/istream:122:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__istream_type& (*)(__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  122 |       operator>>(__istream_type& (*__pf)(__istream_type&))
      |       ^~~~~~~~
/usr/include/c++/14/istream:122:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'std::basic_istream<char>::__istream_type& (*)(std::basic_istream<char>::__istream_type&)' {aka 'std::basic_istream<char>& (*)(std::basic_istream<char>&)'} [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexcept
/usr/include/c++/14/istream:126:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__ios_type& (*)(__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>; __ios_type = std::basic_ios<char>]' (near match)
  126 |       operator>>(__ios_type& (*__pf)(__ios_type&))
      |       ^~~~~~~~
/usr/include/c++/14/istream:126:7: note:   conversion of argument 1 would be ill-formed:
a.cc:74:14: error: invalid conversion from 'double (*)(double) noexcept' to 'std::basic_istream<char>::__ios_type& (*)(std::basic_istream<char>::__ios_type&)' {aka 'std::basic_ios<char>& (*)(std::basic_ios<char>&)'} [-fpermissive]
   74 |     cin>>x1>>y1>>x2>>y2;
      |              ^~
      |              |
      |              double (*)(double) noexc