In file included from /in/driver/main.cpp:5:0:
/in/hashtable.hpp: In member function 'size_t HashTable<Key, Value, Hash, KeyEqual>::findMinimumBucketSize(size_t) const':
/in/hashtable.hpp:171:5: error: no return statement in function returning non-void [-Werror=return-type]
     }
     ^
/in/hashtable.hpp: In instantiation of 'size_t HashTable<Key, Value, Hash, KeyEqual>::findMinimumBucketSize(size_t) const [with Key = int; Value = int; Hash = std::hash<int>; KeyEqual = std::equal_to<int>; size_t = long unsigned int]':
/in/hashtable.hpp:336:43:   required from 'void HashTable<Key, Value, Hash, KeyEqual>::rehash(size_t) [with Key = int; Value = int; Hash = std::hash<int>; KeyEqual = std::equal_to<int>; size_t = long unsigned int]'
/in/hashtable.hpp:264:23:   required from 'bool HashTable<Key, Value, Hash, KeyEqual>::insert(const HashTable<Key, Value, Hash, KeyEqual>::Iterator&, const Key&, const Value&) [with Key = int; Value = int; Hash = std::hash<int>; KeyEqual = std::equal_to<int>]'
/in/hashtable.hpp:272:22:   required from 'bool HashTable<Key, Value, Hash, KeyEqual>::insert(const Key&, const Value&) [with Key = int; Value = int; Hash = std::hash<int>; KeyEqual = std::equal_to<int>]'
/in/driver/main.cpp:111:43:   required from here
/in/hashtable.hpp:169:41: error: unused parameter 'bucketSize' [-Werror=unused-parameter]
     size_t findMinimumBucketSize(size_t bucketSize) const {
                                         ^~~~~~~~~~
cc1plus: all warnings being treated as errors