Language: C++

#include <bits/stdc++.h>
using namespace std;
#define _GLIBCXX_DEBUG
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

int main(){
	int n, m;
	cin >> n;
	map<string, int> mp(n);
	rep(i, n){
		string a;
		cin >> a;
		mp[a]++;
	}
	
	cin >> m;
	rep(i, m){
		string s;
		cin >> s;
		mp[s]--;
	}

	int ans = 0;
	for(pair<string, int> p : mp){
		string key = p.first;
		int value = p.second;
		ans = max(ans, value);
	}
	cout << ans << endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:9:30: error: no matching function for call to 'std::map<std::__cxx11::basic_string<char>, int>::map(int&)'
    9 |         map<string, int> mp(n);
      |                              ^
In file included from /usr/include/c++/14/map:63,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:152,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_map.h:302:9: note: candidate: 'template<class _InputIterator> std::map<_Key, _Tp, _Compare, _Alloc>::map(_InputIterator, _InputIterator, const _Compare&, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  302 |         map(_InputIterator __first, _InputIterator __last,
      |         ^~~
/usr/include/c++/14/bits/stl_map.h:302:9: note:   candidate expects 3 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:285:9: note: candidate: 'template<class _InputIterator> std::map<_Key, _Tp, _Compare, _Alloc>::map(_InputIterator, _InputIterator) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  285 |         map(_InputIterator __first, _InputIterator __last)
      |         ^~~
/usr/include/c++/14/bits/stl_map.h:285:9: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:268:9: note: candidate: 'template<class _InputIterator> std::map<_Key, _Tp, _Compare, _Alloc>::map(_InputIterator, _InputIterator, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  268 |         map(_InputIterator __first, _InputIterator __last,
      |         ^~~
/usr/include/c++/14/bits/stl_map.h:268:9: note:   candidate expects 3 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:262:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::initializer_list<std::pair<const _Key, _Val> >, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  262 |       map(initializer_list<value_type> __l, const allocator_type& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:262:7: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:256:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::map<_Key, _Tp, _Compare, _Alloc>&&, std::__type_identity_t<_Alloc>&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; std::__type_identity_t<_Alloc> = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  256 |       map(map&& __m, const __type_identity_t<allocator_type>& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:256:7: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:252:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const std::map<_Key, _Tp, _Compare, _Alloc>&, std::__type_identity_t<_Alloc>&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; std::__type_identity_t<_Alloc> = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  252 |       map(const map& __m, const __type_identity_t<allocator_type>& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:252:7: note:   candidate expects 2 arguments, 1 provided
/usr/include/c++/14/bits/stl_map.h:248:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  248 |       map(const allocator_type& __a)
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:248:33: note:   no known conversion for argument 1 from 'int' to 'const std::map<std::__cxx11::basic_string<char>, int>::allocator_type&' {aka 'const std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >&'}
  248 |       map(const allocator_type& __a)
      |           ~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:240:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::initializer_list<std::pair<const _Key, _Val> >, const _Compare&, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  240 |       map(initializer_list<value_type> __l,
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:240:40: note:   no known conversion for argument 1 from 'int' to 'std::initializer_list<std::pair<const std::__cxx11::basic_string<char>, int> >'
  240 |       map(initializer_list<value_type> __l,
      |           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/stl_map.h:227:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(std::map<_Key, _Tp, _Compare, _Alloc>&&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  227 |       map(map&&) = default;
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:227:11: note:   no known conversion for argument 1 from 'int' to 'std::map<std::__cxx11::basic_string<char>, int>&&'
  227 |       map(map&&) = default;
      |           ^~~~~
/usr/include/c++/14/bits/stl_map.h:219:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const std::map<_Key, _Tp, _Compare, _Alloc>&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  219 |       map(const map&) = default;
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:219:11: note:   no known conversion for argument 1 from 'int' to 'const std::map<std::__cxx11::basic_string<char>, int>&'
  219 |       map(const map&) = default;
      |           ^~~~~~~~~~
/usr/include/c++/14/bits/stl_map.h:206:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map(const _Compare&, const allocator_type&) [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >; allocator_type = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  206 |       map(const _Compare& __comp,
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:206:27: note:   no known conversion for argument 1 from 'int' to 'const std::less<std::__cxx11::basic_string<char> >&'
  206 |       map(const _Compare& __comp,
      |           ~~~~~~~~~~~~~~~~^~~~~~
/usr/include/c++/14/bits/stl_map.h:197:7: note: candidate: 'std::map<_Key, _Tp, _Compare, _Alloc>::map() [with _Key = std::__cxx11::basic_string<char>; _Tp = int; _Compare = std::less<std::__cxx11::basic_string<char> >; _Alloc = std::allocator<std::pair<const std::__cxx11::basic_string<char>, int> >]'
  197 |       map() = default;
      |       ^~~
/usr/include/c++/14/bits/stl_map.h:197:7: note:   candidate expects 0 arguments, 1 provided