Language: C++

#include<bits/stdc++.h>
using namespace stds;

int mail(){
  int n;
  cin >> n;
  
  for(int i = 0; i < n; i++){
  int c;
  cin >> c;
  
  int P,W,G,Y == 0;
    if(c == "P"){
      P == 1;
    }
    
    if(c == "W"){
      W == 1;
    }
    
    if(c == "G"){
      G == 1;
    }
    
    if(c == "Y"){
      Y == 1;
    }
    
  num = P+W+G+Y;
  if(num==3){
    cout << "Three" << endl;
  }
  if(num==4){
    cout << "Four" << endl;
  }
  }
}

Compiler output:
a.cc:2:17: error: 'stds' is not a namespace-name
    2 | using namespace stds;
      |                 ^~~~
a.cc: In function 'int mail()':
a.cc:6:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    6 |   cin >> n;
      |   ^~~
      |   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:12:15: error: expected initializer before '==' token
   12 |   int P,W,G,Y == 0;
      |               ^~
a.cc:13:10: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   13 |     if(c == "P"){
      |        ~~^~~~~~
a.cc:17:10: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   17 |     if(c == "W"){
      |        ~~^~~~~~
a.cc:21:10: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   21 |     if(c == "G"){
      |        ~~^~~~~~
a.cc:25:10: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   25 |     if(c == "Y"){
      |        ~~^~~~~~
a.cc:26:7: error: 'Y' was not declared in this scope
   26 |       Y == 1;
      |       ^
a.cc:29:3: error: 'num' was not declared in this scope; did you mean 'enum'?
   29 |   num = P+W+G+Y;
      |   ^~~
      |   enum
a.cc:29:15: error: 'Y' was not declared in this scope
   29 |   num = P+W+G+Y;
      |               ^
a.cc:31:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   31 |     cout << "Three" << 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:31:24: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   31 |     cout << "Three" << 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:34:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   34 |     cout << "Four" << 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:34:23: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   34 |     cout << "Four" << endl;
      |                       ^~~~
      |                       std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:37:1: warning: no return statement in function returning non-void [-Wreturn-type]
   37 | }
      | ^