Language: C++

#include <bits/stdc++.h>
#define PI 3.141592653589793238
#define endl '\n'
using namespace std;
int x1, y1, x2, y2, n;
vector<pair<int, int>> pts;
bool has_eq_x = false, has_eq_y = false;
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> x1 >> y1 >> x2 >> y2 >> n;
    for(int i = 0; i < n; i++) {
        int x, y;
        cin >> x >> y;
        if(min(x1, x2) <= x && x <= max(x1, x2)
        && min(y1, y2) <= y && y <= max(y1, y2)) {
            pts.emplace_back(x, y);
            has_eq_x |= x == x1 && x == x2;
            has_eq_y |= y == y1 && y == y2;
        }
    }
    if(has_eq_x || has_eq_y) {
        double ans = 100 * (abs(x2 - x1) + abs(y2 - y1)) - 20 + 10 * PI;
        cout << fixed << setprecision(12) << ans << endl;
    } else {
        sort(pts.begin(), pts.end(), [](auto& a, auto& b) {
            return abs(a.first - x1) + abs(a.second - y1) < abs(b.first - x1) + abs(b.second - y1);
        });
        int curx = x1, cury = y1;
        double ans = 100 * (abs(x2 - x1) + abs(y2 - y1));
        for(auto& p : pts) {
            if(min(curx, x2) <= p.first && p.first <= max(curx, x2)
            && min(cury, y2) <= p.second && p.second <= max(cury, y2)) {
                curx = p.first;
                cury = p.second;
                ans = ans - 20 + 5 * PI;
            }
        }
        cout << fixed << setprecision(12) << ans << endl;
    }
    return 0;
}


Compiler output:
a.cc:5:9: error: 'int y1' redeclared as different kind of entity
    5 | int x1, y1, x2, y2, n;
      |         ^~
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:11:15: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>::__istream_type' {aka 'std::basic_istream<char>'} and 'double(double) noexcept')
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |     ~~~~~~~~~ ^~ ~~
      |         |        |
      |         |        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:11:18: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'double (*)(double) noexcept'
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
/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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'short int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'short unsigned int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'unsigned int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long unsigned int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long long int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'long long unsigned int' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'void*' [-fpermissive]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  double (*)(double) noexcept
a.cc:11:18: 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:11:18: 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]
   11 |     cin >> x1 >> y1 >> x2 >> y2 >> n;
      |                  ^~
      |                  |
      |                  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:11:18: error: invalid conversion from 'double (*)(double) noexcept' to 'std::basic_istream