Language: C++

#include<iostream>
#include<vector>

int main(){
	vector<int> s(100000);
	vector<int> t(50000);
	int n,q,cnt=0;
	for(int i=0;i<n;i++){
		cin>>s[i];
	}
	sort(s.begin(),s.end());
	cin>>q;
	for(int j=0 j<q;j++){
		cin>>t[j];
	}
	for(int k=0;k<q;k++){
		if(binary_search(s.begin(),s.end(),t[k])){
			cnt++;
		}
	}
	cout<<cnt<<endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:5:9: error: 'vector' was not declared in this scope
    5 |         vector<int> s(100000);
      |         ^~~~~~
a.cc:5:9: 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:5:16: error: expected primary-expression before 'int'
    5 |         vector<int> s(100000);
      |                ^~~
a.cc:6:16: error: expected primary-expression before 'int'
    6 |         vector<int> t(50000);
      |                ^~~
a.cc:9:17: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    9 |                 cin>>s[i];
      |                 ^~~
      |                 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:9:22: error: 's' was not declared in this scope
    9 |                 cin>>s[i];
      |                      ^
a.cc:11:14: error: 's' was not declared in this scope
   11 |         sort(s.begin(),s.end());
      |              ^
a.cc:11:9: error: 'sort' was not declared in this scope; did you mean 'short'?
   11 |         sort(s.begin(),s.end());
      |         ^~~~
      |         short
a.cc:12:9: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
   12 |         cin>>q;
      |         ^~~
      |         std::cin
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:13:20: error: expected ';' before 'j'
   13 |         for(int j=0 j<q;j++){
      |                    ^~
      |                    ;
a.cc:14:22: error: 't' was not declared in this scope
   14 |                 cin>>t[j];
      |                      ^
a.cc:17:52: error: 't' was not declared in this scope
   17 |                 if(binary_search(s.begin(),s.end(),t[k])){
      |                                                    ^
a.cc:17:20: error: 'binary_search' was not declared in this scope
   17 |                 if(binary_search(s.begin(),s.end(),t[k])){
      |                    ^~~~~~~~~~~~~
a.cc:21:9: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   21 |         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:21:20: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   21 |         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)
      |     ^~~~