Language: C++

#include<>
using namespace std;

int main()
{
    int x;
    cin>>x;
    if(x>=400&&x<=599)
    {
        cout<<8<<endl;
    }
    else if(x>=600&&x<=799)
    {
        cout<<7<<endl;
    }
    else if(x>=800&&x<=999)
    {
        cout<<6<<endl;
    }
    else if(x>=1000&&x<=1199)
    {
        cout<<5<<endl;
    }
    else if(x>=1200&&x<=1399)
    {
        cout<<4<<endl;
    }
    else if(x>=1400&&x<=1599)
    {
        cout<<3<<endl;
    }
    else if(x>=1600&&x<=1799)
    {
        cout<<2<<endl;
    }
    else if(x>=1800&&x<=1999)
    {
        cout<<1<<endl;
    }
    return 0;
}

Compiler output:
a.cc:1:9: error: empty filename in #include
    1 | #include<>
      |         ^~
a.cc: In function 'int main()':
a.cc:7:5: error: 'cin' was not declared in this scope
    7 |     cin>>x;
      |     ^~~
a.cc:1:1: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
  +++ |+#include <iostream>
    1 | #include<>
a.cc:10:9: error: 'cout' was not declared in this scope
   10 |         cout<<8<<endl;
      |         ^~~~
a.cc:10:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:10:18: error: 'endl' was not declared in this scope
   10 |         cout<<8<<endl;
      |                  ^~~~
a.cc:1:1: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
  +++ |+#include <ostream>
    1 | #include<>
a.cc:14:9: error: 'cout' was not declared in this scope
   14 |         cout<<7<<endl;
      |         ^~~~
a.cc:14:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:14:18: error: 'endl' was not declared in this scope
   14 |         cout<<7<<endl;
      |                  ^~~~
a.cc:14:18: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
a.cc:18:9: error: 'cout' was not declared in this scope
   18 |         cout<<6<<endl;
      |         ^~~~
a.cc:18:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:18:18: error: 'endl' was not declared in this scope
   18 |         cout<<6<<endl;
      |                  ^~~~
a.cc:18:18: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
a.cc:22:9: error: 'cout' was not declared in this scope
   22 |         cout<<5<<endl;
      |         ^~~~
a.cc:22:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:22:18: error: 'endl' was not declared in this scope
   22 |         cout<<5<<endl;
      |                  ^~~~
a.cc:22:18: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
a.cc:26:9: error: 'cout' was not declared in this scope
   26 |         cout<<4<<endl;
      |         ^~~~
a.cc:26:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:26:18: error: 'endl' was not declared in this scope
   26 |         cout<<4<<endl;
      |                  ^~~~
a.cc:26:18: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
a.cc:30:9: error: 'cout' was not declared in this scope
   30 |         cout<<3<<endl;
      |         ^~~~
a.cc:30:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:30:18: error: 'endl' was not declared in this scope
   30 |         cout<<3<<endl;
      |                  ^~~~
a.cc:30:18: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
a.cc:34:9: error: 'cout' was not declared in this scope
   34 |         cout<<2<<endl;
      |         ^~~~
a.cc:34:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:34:18: error: 'endl' was not declared in this scope
   34 |         cout<<2<<endl;
      |                  ^~~~
a.cc:34:18: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
a.cc:38:9: error: 'cout' was not declared in this scope
   38 |         cout<<1<<endl;
      |         ^~~~
a.cc:38:9: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc:38:18: error: 'endl' was not declared in this scope
   38 |         cout<<1<<endl;
      |                  ^~~~
a.cc:38:18: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'