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- /*
- * Frozen
- * Copyright 2016 QuarksLab
- *
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements. See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership. The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied. See the License for the
- * specific language governing permissions and limitations
- * under the License.
- */
-
- #ifndef FROZEN_LETITGO_UNORDERED_SET_H
- #define FROZEN_LETITGO_UNORDERED_SET_H
-
- #include "frozen/bits/basic_types.h"
- #include "frozen/bits/constexpr_assert.h"
- #include "frozen/bits/elsa.h"
- #include "frozen/bits/pmh.h"
- #include "frozen/bits/version.h"
- #include "frozen/random.h"
-
- #include <utility>
-
- namespace frozen {
-
- namespace bits {
-
- struct Get {
- template <class T> constexpr T const &operator()(T const &key) const {
- return key;
- }
- };
-
- } // namespace bits
-
- template <class Key, std::size_t N, typename Hash = elsa<Key>,
- class KeyEqual = std::equal_to<Key>>
- class unordered_set {
- static constexpr std::size_t storage_size =
- bits::next_highest_power_of_two(N) * (N < 32 ? 2 : 1); // size adjustment to prevent high collision rate for small sets
- using container_type = bits::carray<Key, N>;
- using tables_type = bits::pmh_tables<storage_size, Hash>;
-
- KeyEqual const equal_;
- container_type keys_;
- tables_type tables_;
-
- public:
- /* typedefs */
- using key_type = Key;
- using value_type = Key;
- using size_type = typename container_type::size_type;
- using difference_type = typename container_type::difference_type;
- using hasher = Hash;
- using key_equal = KeyEqual;
- using const_reference = typename container_type::const_reference;
- using reference = const_reference;
- using const_pointer = typename container_type::const_pointer;
- using pointer = const_pointer;
- using const_iterator = const_pointer;
- using iterator = const_iterator;
-
- public:
- /* constructors */
- unordered_set(unordered_set const &) = default;
- constexpr unordered_set(container_type keys, Hash const &hash,
- KeyEqual const &equal)
- : equal_{equal}
- , keys_{keys}
- , tables_{bits::make_pmh_tables<storage_size>(
- keys_, hash, bits::Get{}, default_prg_t{})} {}
- explicit constexpr unordered_set(container_type keys)
- : unordered_set{keys, Hash{}, KeyEqual{}} {}
-
- constexpr unordered_set(std::initializer_list<Key> keys)
- : unordered_set{keys, Hash{}, KeyEqual{}} {}
-
- constexpr unordered_set(std::initializer_list<Key> keys, Hash const & hash, KeyEqual const & equal)
- : unordered_set{container_type{keys}, hash, equal} {
- constexpr_assert(keys.size() == N, "Inconsistent initializer_list size and type size argument");
- }
-
- /* iterators */
- constexpr const_iterator begin() const { return keys_.begin(); }
- constexpr const_iterator end() const { return keys_.end(); }
- constexpr const_iterator cbegin() const { return keys_.cbegin(); }
- constexpr const_iterator cend() const { return keys_.cend(); }
-
- /* capacity */
- constexpr bool empty() const { return !N; }
- constexpr size_type size() const { return N; }
- constexpr size_type max_size() const { return N; }
-
- /* lookup */
- constexpr std::size_t count(Key const &key) const {
- auto const k = lookup(key);
- return equal_(k, key);
- }
- constexpr const_iterator find(Key const &key) const {
- auto const &k = lookup(key);
- if (equal_(k, key))
- return &k;
- else
- return keys_.end();
- }
-
- constexpr std::pair<const_iterator, const_iterator> equal_range(Key const &key) const {
- auto const &k = lookup(key);
- if (equal_(k, key))
- return {&k, &k + 1};
- else
- return {keys_.end(), keys_.end()};
- }
-
- /* bucket interface */
- constexpr std::size_t bucket_count() const { return storage_size; }
- constexpr std::size_t max_bucket_count() const { return storage_size; }
-
- /* observers*/
- constexpr hasher hash_function() const { return tables_.hash_; }
- constexpr key_equal key_eq() const { return equal_; }
-
- private:
- constexpr auto const &lookup(Key const &key) const {
- return keys_[tables_.lookup(key)];
- }
- };
-
- template <typename T, std::size_t N>
- constexpr auto make_unordered_set(T const (&keys)[N]) {
- return unordered_set<T, N>{keys};
- }
-
- } // namespace frozen
-
- #endif
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