In file included from /in/driver/main.cpp:5:0:
/in/hashtable.hpp: In instantiation of 'HashTable<Key, Value, Hash, KeyEqual>::Iterator HashTable<Key, Value, Hash, KeyEqual>::find(const Key&) [with Key = int; Value = int; Hash = std::hash<int>; KeyEqual = std::equal_to<int>]':
/in/driver/main.cpp:101:34:   required from here
/in/hashtable.hpp:232:13: error: no match for call to '(std::equal_to<int>) (std::_Fwd_list_iterator<std::pair<const int, int> >&, const int&)'
             if (keyEqual(itBefore,key)){
             ^~
In file included from /usr/include/c++/7/string:48:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from /in/driver/main.cpp:1:
/usr/include/c++/7/bits/stl_function.h:355:7: note: candidate: constexpr bool std::equal_to<_Tp>::operator()(const _Tp&, const _Tp&) const [with _Tp = int]
       operator()(const _Tp& __x, const _Tp& __y) const
       ^~~~~~~~
/usr/include/c++/7/bits/stl_function.h:355:7: note:   no known conversion for argument 1 from 'std::_Fwd_list_iterator<std::pair<const int, int> >' to 'const int&'