Language: C++

#include <bits/stdc++.h>
#define ll long long int
#define ld long double
#define f first
#define s second
#define pb push_back
#define eb emplace_back
#define mk make_pair
#define mt make_tuple
#define MOD 1000000007
#define fo(i,a,b) for(i=a;i<b;i++)
#define foe(i,a,b) for(i=a;i<=b;i++)
#define all(x) x.begin(), x.end()
#define vi vector<int>
#define vl vector <long long int>
#define pii pair <int,int>
#define pll pair <long long int, long long int>
#define vpii vector< pair<int,int> >
#define vpll vector < pair <long long int,long long int> >
#define boost ios::sync_with_stdio(false); cin.tie(0)
using namespace std;
const int inf = 1e9 + 5;
const ll inf64 = 1e18 + 5;

int n, m, k, x1, y1, x2, y2;
map <pii, int> mp1, mp2;
map <pii, bool> vis;
vector <vector <char> > v;
void bfs(pii p, map <pii, int> &mp)
{
	vis[p] = true;
	mp[p] = 0;
	queue <pii> q;
	q.push(p);
	while(!q.empty()) {
		pii p = q.front();
		q.pop();
		
		for(int i = p.f + 1; i <= min(n - 1, p.f + k); i++) {
			pii to = {i, p.s};
			if(v[to.f][to.s] == '@' || vis[to]) break;
			
			vis[to] = true;
			mp[to] = mp[p] + 1;
			q.push(to);
		}
		for(int i = p.s + 1; i <= min(m - 1, p.s + k); i++) {
			pii to = {p.f, i};
			if(v[to.f][to.s] == '@' || vis[to]) break;
			
			vis[to] = true;
			mp[to] = mp[p] + 1;
			q.push(to);
		}
		for(int i = p.f - 1; i >= max(0, p.f - k); i--) {
			pii to = {i, p.s};
			if(v[to.f][to.s] == '@' || vis[to]) break;
			
			vis[to] = true;
			mp[to] = mp[p] + 1;
			q.push(to);
		}
		for(int i = p.s - 1; i >= max(0, p.s - k); i--) {
			pii to = {p.f, i};
			if(v[to.f][to.s] == '@' || vis[to]) break;
			
			vis[to] = true;
			mp[to] = mp[p] + 1;
			q.push(to);
		}
	}
}
int main()
{
	boost;
	cin >> n >> m >> k;
	cin >> x1 >> y1 >> x2 >> y2;
	--x1, --y1, --x2, --y2;
	v.resize(n, vector <char> (m, '0'));
	for(int i = 0; i < n; i++) {
		for(int j = 0; j < m; j++)
		cin >> v[i][j];
	}
	bfs(mk(x1, y1), mp1);
	if(!mp1[{x2, y2}]) cout << -1;
	else {
		vis.clear();
		bfs(mk(x2, y2), mp2);
		int ans = inf;
		for(int i = 0; i < n; i++) {
			for(int j = 0; j < n; j++) {
				if(v[i][j] == '@') continue;
				ans = min(ans, mp1[{i, j}] + mp2[{i, j}]);
			}
		}
		cout << ans;
	}
}


Compiler output:
a.cc:25:18: error: 'int y1' redeclared as different kind of entity
   25 | 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:77:19: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   77 |         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:77:22: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   77 |         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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   77 |         cin >> x1 >> y1 >> x2 >> y2;
      |                      ^~
      |                      |
      |                      double (*)(double) noexcept
a.cc:77:22: 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:77:22: 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]
   77 |         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