Language: C++

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

int main()
{
  long long n, a, b;
  cin >> n >> a >> b;
  if(a == b)
    cout << 0 << endl;
  else
  {
    long long temp = abs(a - b);
    if(temp & 1)
    {
      long long x = max(a - 1LL, b - 1LL);
      long long y = max(n - a, n - b);
      cout << min(x, y) << endl;
    }
    else
    {
      cout << (temp >> 1) << endl;
    }
  }
  return 0;
}

Compiler output:
a.cc:2:7: error: expected nested-name-specifier before 'namespce'
    2 | using namespce std;
      |       ^~~~~~~~
a.cc: In function 'int main()':
a.cc:7:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    7 |   cin >> n >> a >> b;
      |   ^~~
      |   std::cin
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:146,
                 from a.cc:1:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:9:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
    9 |     cout << 0 << endl;
      |     ^~~~
      |     std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:9:18: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
    9 |     cout << 0 << endl;
      |                  ^~~~
      |                  std::endl
In file included from /usr/include/c++/14/istream:41,
                 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/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:15:21: error: 'max' was not declared in this scope; did you mean 'std::max'?
   15 |       long long x = max(a - 1LL, b - 1LL);
      |                     ^~~
      |                     std::max
In file included from /usr/include/c++/14/algorithm:61,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: 'std::max' declared here
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
a.cc:17:7: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   17 |       cout << min(x, y) << endl;
      |       ^~~~
      |       std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:17:15: error: 'min' was not declared in this scope; did you mean 'std::min'?
   17 |       cout << min(x, y) << endl;
      |               ^~~
      |               std::min
/usr/include/c++/14/bits/stl_algo.h:5696:5: note: 'std::min' declared here
 5696 |     min(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
a.cc:17:28: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   17 |       cout << min(x, y) << endl;
      |                            ^~~~
      |                            std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:21:7: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   21 |       cout << (temp >> 1) << endl;
      |       ^~~~
      |       std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:21:30: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   21 |       cout << (temp >> 1) << endl;
      |                              ^~~~
      |                              std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~