Language: C++

    /*
    https://t.me/unstoppabIesoIvemachinechannel
    */
    #pragma ARCENIY_KIRILLOV_POVELITEL_KROKODILOV
    //#pragma comment(linker, "/stack:200000000")
    //#pragma GCC optimize("Ofast")
    //#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
    //#pragma GCC optimize("no-stack-protector")
    //#pragma GCC push_options
    //#pragma GCC optimize ("unroll-loops")
    //#pragma GCC pop_options
    //#pragma GCC target("popcnt")
    //#pragma GCC target("sse4")
    #include<bits/stdc++.h>
    #define fi first
    #define se second
    #define pb push_back
    #define eb emplace_back
    #define rng(a) a.begin(),a.end()
    #define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
    #define rep(i, n) for (int i = 0; i < n; i++)
    #define per(i, n) for (int i = n - 1; i > -1; i--)
    #define rer(i, x, n) for (int i = x; i < n; i++)
    using namespace std;
    typedef long long ll;
    typedef pair<int, int> pii;
    typedef vector<int> vi;
    typedef vector<vi> vvi;
    typedef vector<pii> vp;
    typedef long double ld;
     
     
     
     
     
     
     
     
     
     
     
     
    signed main(){
        int n;
        cin >> n;
        string s = "", q = "";
        for (int i = 0; i < n; i++){
            char c;
            cin >> c;
            s += c;
        }
        for (int i = 0; i < n; i++){
            char c;
            cin >> c;
            q += c;
        }
        reverse(rng(q));
        int kek = (1 << n);
        unordered_map<pair<string,string>, int> m;
        for (int i = 0; i < kek; i++){
            string t = "";
            string f = "";
            for (int j = 0; j < n; j++){
                if (i & (1 << j)){
                    t += s[j];
                }else f += s[j];
                m[{t,f}]++;
            }
        }
        ll ans = 0;
        for (int i = 0; i < kek; i++){
            string t = "";
            string f = "";
            for (int j = 0; j < n; j++){
                if (i & (1 << j)){
                    t += q[j];
                }else f += q[j];
            }
                ans += m[{t,f}];
        }
        cout << ans;
    }

Compiler output:
a.cc: In function 'int main()':
a.cc:59:49: error: use of deleted function 'std::unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Tp = int; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Pred = std::equal_to<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Alloc = std::allocator<std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int> >]'
   59 |         unordered_map<pair<string,string>, int> m;
      |                                                 ^
In file included from /usr/include/c++/14/unordered_map:41,
                 from /usr/include/c++/14/functional:63,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:53,
                 from a.cc:14:
/usr/include/c++/14/bits/unordered_map.h:148:7: note: 'std::unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>::unordered_map() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Tp = int; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Pred = std::equal_to<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Alloc = std::allocator<std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int> >]' is implicitly deleted because the default definition would be ill-formed:
  148 |       unordered_map() = default;
      |       ^~~~~~~~~~~~~
/usr/include/c++/14/bits/unordered_map.h: At global scope:
/usr/include/c++/14/bits/unordered_map.h:148:7: error: use of deleted function 'std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits>::_Hashtable() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Value = std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int>; _Alloc = std::allocator<std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int> >; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<true, false, true>]'
In file included from /usr/include/c++/14/bits/unordered_map.h:33:
/usr/include/c++/14/bits/hashtable.h:539:7: note: 'std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _RehashPolicy, _Traits>::_Hashtable() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Value = std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int>; _Alloc = std::allocator<std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int> >; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<true, false, true>]' is implicitly deleted because the default definition would be ill-formed:
  539 |       _Hashtable() = default;
      |       ^~~~~~~~~~
/usr/include/c++/14/bits/hashtable.h:539:7: error: use of deleted function 'std::__detail::_Hashtable_base<_Key, _Value, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _Traits>::_Hashtable_base() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Value = std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _Traits = std::__detail::_Hashtable_traits<true, false, true>]'
In file included from /usr/include/c++/14/bits/hashtable.h:35:
/usr/include/c++/14/bits/hashtable_policy.h:1731:7: note: 'std::__detail::_Hashtable_base<_Key, _Value, _ExtractKey, _Equal, _Hash, _RangeHash, _Unused, _Traits>::_Hashtable_base() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Value = std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; _Traits = std::__detail::_Hashtable_traits<true, false, true>]' is implicitly deleted because the default definition would be ill-formed:
 1731 |       _Hashtable_base() = default;
      |       ^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1731:7: error: use of deleted function 'std::__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Hash, _RangeHash, _Unused, __cache_hash_code>::_Hash_code_base() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Value = std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int>; _ExtractKey = std::__detail::_Select1st; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; bool __cache_hash_code = true]'
/usr/include/c++/14/bits/hashtable_policy.h: In instantiation of 'std::__detail::_Hashtable_ebo_helper<_Nm, _Tp, true>::_Hashtable_ebo_helper() [with int _Nm = 1; _Tp = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >]':
/usr/include/c++/14/bits/hashtable_policy.h:1328:7:   required from here
 1328 |       _Hash_code_base() = default;
      |       ^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1245:49: error: use of deleted function 'std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >::hash()'
 1245 |       _Hashtable_ebo_helper() noexcept(noexcept(_Tp())) : _Tp() { }
      |                                                 ^~~~~
In file included from /usr/include/c++/14/string_view:50,
                 from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52:
/usr/include/c++/14/bits/functional_hash.h:102:12: note: 'std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >::hash()' is implicitly deleted because the default definition would be ill-formed:
  102 |     struct hash : __hash_enum<_Tp>
      |            ^~~~
/usr/include/c++/14/bits/functional_hash.h:102:12: error: no matching function for call to 'std::__hash_enum<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, false>::__hash_enum()'
/usr/include/c++/14/bits/functional_hash.h:83:7: note: candidate: 'std::__hash_enum<_Tp, <anonymous> >::__hash_enum(std::__hash_enum<_Tp, <anonymous> >&&) [with _Tp = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; bool <anonymous> = false]'
   83 |       __hash_enum(__hash_enum&&);
      |       ^~~~~~~~~~~
/usr/include/c++/14/bits/functional_hash.h:83:7: note:   candidate expects 1 argument, 0 provided
/usr/include/c++/14/bits/functional_hash.h:102:12: error: 'std::__hash_enum<_Tp, <anonymous> >::~__hash_enum() [with _Tp = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; bool <anonymous> = false]' is private within this context
  102 |     struct hash : __hash_enum<_Tp>
      |            ^~~~
/usr/include/c++/14/bits/functional_hash.h:84:7: note: declared private here
   84 |       ~__hash_enum();
      |       ^
/usr/include/c++/14/bits/hashtable_policy.h:1245:49: note: use '-fdiagnostics-all-candidates' to display considered candidates
 1245 |       _Hashtable_ebo_helper() noexcept(noexcept(_Tp())) : _Tp() { }
      |                                                 ^~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1328:7: note: 'std::__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Hash, _RangeHash, _Unused, __cache_hash_code>::_Hash_code_base() [with _Key = std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >; _Value = std::pair<const std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> >, int>; _ExtractKey = std::__detail::_Select1st; _Hash = std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >; _RangeHash = std::__detail::_Mod_range_hashing; _Unused = std::__detail::_Default_ranged_hash; bool __cache_hash_code = true]' is implicitly deleted because the default definition would be ill-formed:
 1328 |       _Hash_code_base() = default;
      |       ^~~~~~~~~~~~~~~
/usr/include/c++/14/bits/hashtable_policy.h:1328:7: error: use of deleted function 'std::__detail::_Hashtable_ebo_helper<1, std::hash<std::pair<std::__cxx11::basic_string<char>, std::__cxx11::basic_string<char> > >, true>::~_Hashtable_ebo_helper()'
/usr/include/c++/14/bits/hashtable_policy.h:1242:12: note: 'std::__detail::_Hashtable_ebo_helper<1, std::hash<std::pair<std::__cxx11::basic_strin