Language: C++

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
#define orderd_set tree<pair<int, int>, null_type,greater<pair<int, int>>, rb_tree_tag,tree_order_statistics_node_update>
//find_by_order(k)
//order_of_key(k)
#define FIO ios_base::sync_with_stdio(0);cin.tie(0);
const int N = 2e3+69;
#define ALL(x) begin(x),end(x)
#define sz(x) (ll)x.size()
const int OO = 0x3f3f3f3f;
const int mod = 1000000007;

int n, m, k,x1, y1 ,x2 ,y2;
char grid[1069][1069];
int dis[1069][1069];
int mvx[] = {1, -1, 0, 0};
int mvy[] = {0, 0, 1, -1};



bool valid(int x, int y)
{
    return x < n && x >= 0 && y < m && y >= 0 && grid[x][y] == '.';
}


void bfs(int sx, int sy)
{
    queue<pair<int, int>> q;
    q.push({sx, sy});
    dis[sx][sy] = 0;
    while(sz(q))
    {
        int ux = q.front().first;
        int uy = q.front().second;
        q.pop();
        for(int i = 0; i< 4; i++)
        {
            for(int j = 1; j<= k; j++)
            {
                int vx = ux + mvx[i]*j;
                int vy = uy + mvy[i]*j;
                if(valid(vx, vy) && dis[vx][vy] >= dis[ux][uy]+1)
                {
                    dis[vx][vy] = dis[ux][uy]+1;
                    q.push({vx, vy});
                }
                else
                    break;
            }
        }
    }
}



int main()
{
    FIO
    cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
    memset(dis, OO, sizeof dis);
    for(int i = 0; i< n; i++)
    {
        for(int j = 0; j< m; j++)
        {
            cin >> grid[i][j];
        }
    }
    x1--;x2--;y1--;y2--;
    bfs(x1, y1);
//    for(int i = 0; i< n; i++)
//    {
//        for(int j = 0; j< m; j++)
//        {
//            cout << dis[i][j] << "          ";
//        }
//        cout << "\n";
//    }
    if(dis[x2][y2] == OO)
        cout << -1 << "\n";
    else
        cout << dis[x2][y2] << "\n";
    return 0;
}


Compiler output:
a.cc:17:17: error: 'int y1' redeclared as different kind of entity
   17 | int n, m, k,x1, y1 ,x2 ,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:64:30: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   64 |     cin >> n >> m >> k >> 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:64:33: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   64 |     cin >> n >> m >> k >> 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |
      |                                 double (*)(double) noexcept
a.cc:64:33: 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:64:33: 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]
   64 |     cin >> n >> m >> k >> x1 >> y1 >> x2 >> y2;
      |                                 ^~
      |                                 |