Language: C++

#include <bits/stdc++.h>
using namespace std;

struct S {
	int d, x, y, v, l;
	S();
	S(int d, int x, int y, int v, int l) :
			d(d), x(x), y(y), v(v), l(l) {
	}
	;
};

auto c = [](S a, S b) {
	return a.d > b.d;
};

int h, w, k, x1, x2, y1, y2, v[][2] =
		{ { 1, 0 }, { 0, 1 }, { -1, 0 }, { 0, -1 } };
priority_queue<S, vector<S>, decltype(c)> q(c);

int main() {
	cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
	bool b[h + 2][w + 2];
	fill(b[0], b[h + 2], 0);
	for (int i = 0; i < h; ++i) {
		string s;
		cin >> s;
		for (int j = 0; j < w; ++j)
			if (s[j] == '.')
				b[i + 1][j + 1] = 1;
	}

	int d[h + 2][w + 2];
	fill(d[1], d[h + 1], h * w);
	d[x1][x2] = 0;

	q.emplace(0, x1, y1, -1, k);

	while (!q.empty()) {
		S s = q.top();
		q.pop();
		if (s.x == x2 && s.y == y2) {
			cout << s.d << endl;
			return 0;
		}
		if (s.d > d[s.x][s.y] + 1)
			continue;
		if (s.d < d[s.x][s.y])
			d[s.x][s.y] = s.d;

		for (int i = 0; i < 4; ++i) {
			if ((i + 2) % 4 == s.v)
				continue;
			int nx = s.x + v[i][0];
			int ny = s.y + v[i][1];
			if (!b[nx][ny])
				continue;
			int nd = s.d + 1;
			if (s.v == i && s.l < k)
				--nd;
			int nl = (s.v == i ? s.l % k + 1 : 1);
			q.emplace(nd, nx, ny, i, nl);
		}
	}
	cout << -1 << endl;
}


Compiler output:
a.cc:17:22: error: 'int y1' redeclared as different kind of entity
   17 | int h, w, k, x1, x2, y1, y2, v[][2] =
      |                      ^~
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:22:34: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   22 |         cin >> h >> w >> 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:22:37: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   22 |         cin >> h >> w >> 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   22 |         cin >> h >> w >> k >> x1 >> y1 >> x2 >> y2;
      |                                     ^~
      |                                     |
      |                                     double (*)(double) noexcept
a.cc:22:37: 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:22:37: 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