Language: C++

#include <bits/stdc++.h>
int main()
{
 int a,b,c;
 cin>>a>>b>>c;
 vector<int> v;
 v.push_back(a);
 v.push_back(b);
 v.push_back(c);
 sort(v.begin(),v.end());
 for(int i=0;i<v.size();i++){
  if(i) cout<<" "
   else cout<<v[i];
 }
 cout<<endl;
}
 

Compiler output:
a.cc: In function 'int main()':
a.cc:5:2: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    5 |  cin>>a>>b>>c;
      |  ^~~
      |  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:6:2: error: 'vector' was not declared in this scope
    6 |  vector<int> v;
      |  ^~~~~~
a.cc:6:2: note: suggested alternatives:
In file included from /usr/include/c++/14/vector:66,
                 from /usr/include/c++/14/functional:64,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:53:
/usr/include/c++/14/bits/stl_vector.h:428:11: note:   'std::vector'
  428 |     class vector : protected _Vector_base<_Tp, _Alloc>
      |           ^~~~~~
/usr/include/c++/14/vector:93:13: note:   'std::pmr::vector'
   93 |       using vector = std::vector<_Tp, polymorphic_allocator<_Tp>>;
      |             ^~~~~~
a.cc:6:9: error: expected primary-expression before 'int'
    6 |  vector<int> v;
      |         ^~~
a.cc:7:2: error: 'v' was not declared in this scope
    7 |  v.push_back(a);
      |  ^
a.cc:10:2: error: 'sort' was not declared in this scope; did you mean 'std::sort'?
   10 |  sort(v.begin(),v.end());
      |  ^~~~
      |  std::sort
In file included from /usr/include/c++/14/algorithm:86,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/pstl/glue_algorithm_defs.h:296:1: note: 'std::sort' declared here
  296 | sort(_ExecutionPolicy&& __exec, _RandomAccessIterator __first, _RandomAccessIterator __last);
      | ^~~~
a.cc:12:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   12 |   if(i) cout<<" "
      |         ^~~~
      |         std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:15:2: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   15 |  cout<<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:15:8: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   15 |  cout<<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)
      |     ^~~~