Language: C++

#include<iostream>
#include<vector>
#include<algorithm>
usign namespace std;

int main()
{
  int N,cnt=1;
  cin>>N;
  vector<int> d(N);
  for(int ni=0;ni<N;ni++)
  {
    cin>>d.at(ni);
  }
  sort(d.begin(),d.end());
  if(N==1)
  {
    cout<<cnt<<endl;
    return 0;
  }
  for(int nj =1 ;nj<N;nj++)
  {
    if(d.at(nj-1)!=d.at(nj))
      cnt++;
  }
  cout<<cnt<<endl;
  return 0;
}

      
      

Compiler output:
a.cc:4:1: error: 'usign' does not name a type
    4 | usign namespace std;
      | ^~~~~
a.cc: In function 'int main()':
a.cc:9:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    9 |   cin>>N;
      |   ^~~
      |   std::cin
In file included 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:10:3: error: 'vector' was not declared in this scope
   10 |   vector<int> d(N);
      |   ^~~~~~
a.cc:10:3: note: suggested alternatives:
In file included from /usr/include/c++/14/vector:66,
                 from a.cc:2:
/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:10:10: error: expected primary-expression before 'int'
   10 |   vector<int> d(N);
      |          ^~~
a.cc:13:10: error: 'd' was not declared in this scope
   13 |     cin>>d.at(ni);
      |          ^
a.cc:15:8: error: 'd' was not declared in this scope
   15 |   sort(d.begin(),d.end());
      |        ^
a.cc:15:3: error: 'sort' was not declared in this scope; did you mean 'std::sort'?
   15 |   sort(d.begin(),d.end());
      |   ^~~~
      |   std::sort
In file included from /usr/include/c++/14/algorithm:86,
                 from a.cc:3:
/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:18:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   18 |     cout<<cnt<<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:18:16: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   18 |     cout<<cnt<<endl;
      |                ^~~~
      |                std::endl
In file included from /usr/include/c++/14/iostream:41:
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:26:3: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   26 |   cout<<cnt<<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:26:14: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   26 |   cout<<cnt<<endl;
      |              ^~~~
      |              std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~