Language: C++

#pragma GCC optimize ("O3")
#include <bits/stdc++.h>
#define ll long long
#define ld long double
using namespace std;
ld x1, y1, x2, y2, x3, y3, x4, y4, dy, dx;
int main()
{
    ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    cin >> x1 >> y1 >> x2 >> y2;
    dy = abs(y2 - y1), dx = abs(x2 - x1);
    if(y1 > y2 && x1 >= x2){
        x3 = x2 + dy, y3 = y2 - dx;
        x4 = x1 + dy, y4 = y1 - dx;
    }
    else if(x2 > x1 && y1 >= y2){
        x3 = x2 + dy, y3 = y2 + dx;
        x4 = x1 + dy, y4 = y1 + dx;
    }
    else if(y2 > y1 && x2 >= x1){
        x3 = x2 - dy, y3 = y2 + dx;
        x4 = x1 - dy, y4 = y1 + dx;
    }
    else if(x1 > x2 && y2 >= y1){
        x3 = x2 - dy, y3 = y2 - dx;
        x4 = x1 - dy, y4 = y1 - dx;
    }
    cout << x3 << ' ' << y3 << ' ' << x4 << ' ' << y4;
    return 0;
}


Compiler output:
a.cc:6:8: error: 'long double y1' redeclared as different kind of entity
    6 | ld x1, y1, x2, y2, x3, y3, x4, y4, dy, dx;
      |        ^~
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:2:
/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:10:15: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   10 |     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:10:18: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   10 |     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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   10 |     cin >> x1 >> y1 >> x2 >> y2;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:10:18: 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:10:18: 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]
   10 |     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:10:18: error: invalid conversion from 'double (*)(double) noexcept' to 'std::basic_istream<char>::__ios_type& (*)(std::basi