--- /dev/null
+// -*- C++ -*-
+
+// Copyright (C) 2005, 2006, 2009, 2010, 2011 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the terms
+// of the GNU General Public License as published by the Free Software
+// Foundation; either version 3, or (at your option) any later
+// version.
+
+// This library is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+// <http://www.gnu.org/licenses/>.
+
+// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
+
+// Permission to use, copy, modify, sell, and distribute this software
+// is hereby granted without fee, provided that the above copyright
+// notice appears in all copies, and that both that copyright notice
+// and this permission notice appear in supporting documentation. None
+// of the above authors, nor IBM Haifa Research Laboratories, make any
+// representation about the suitability of this software for any
+// purpose. It is provided "as is" without express or implied
+// warranty.
+
+/**
+ * @file hash_policy.hpp
+ * Contains hash-related policies.
+ */
+
+#ifndef PB_DS_HASH_POLICY_HPP
+#define PB_DS_HASH_POLICY_HPP
+
+#include <bits/c++config.h>
+#include <algorithm>
+#include <vector>
+#include <cmath>
+#include <ext/pb_ds/exception.hpp>
+#include <ext/pb_ds/detail/type_utils.hpp>
+#include <ext/pb_ds/detail/hash_fn/mask_based_range_hashing.hpp>
+#include <ext/pb_ds/detail/hash_fn/mod_based_range_hashing.hpp>
+#include <ext/pb_ds/detail/resize_policy/hash_load_check_resize_trigger_size_base.hpp>
+
+namespace __gnu_pbds
+{
+#define PB_DS_CLASS_T_DEC template<typename Size_Type>
+#define PB_DS_CLASS_C_DEC linear_probe_fn<Size_Type>
+
+ /// A probe sequence policy using fixed increments.
+ template<typename Size_Type = std::size_t>
+ class linear_probe_fn
+ {
+ public:
+ typedef Size_Type size_type;
+
+ void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ protected:
+ /// Returns the i-th offset from the hash value.
+ inline size_type
+ operator()(size_type i) const;
+ };
+
+#include <ext/pb_ds/detail/hash_fn/linear_probe_fn_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+#define PB_DS_CLASS_T_DEC template<typename Size_Type>
+#define PB_DS_CLASS_C_DEC quadratic_probe_fn<Size_Type>
+
+ /// A probe sequence policy using square increments.
+ template<typename Size_Type = std::size_t>
+ class quadratic_probe_fn
+ {
+ public:
+ typedef Size_Type size_type;
+
+ void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ protected:
+ /// Returns the i-th offset from the hash value.
+ inline size_type
+ operator()(size_type i) const;
+ };
+
+#include <ext/pb_ds/detail/hash_fn/quadratic_probe_fn_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+#define PB_DS_CLASS_T_DEC template<typename Size_Type>
+#define PB_DS_CLASS_C_DEC direct_mask_range_hashing<Size_Type>
+
+ /// A mask range-hashing class (uses a bitmask).
+ template<typename Size_Type = std::size_t>
+ class direct_mask_range_hashing
+ : public detail::mask_based_range_hashing<Size_Type>
+ {
+ private:
+ typedef detail::mask_based_range_hashing<Size_Type> mask_based_base;
+
+ public:
+ typedef Size_Type size_type;
+
+ void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ protected:
+ void
+ notify_resized(size_type size);
+
+ /// Transforms the __hash value hash into a ranged-hash value
+ /// (using a bit-mask).
+ inline size_type
+ operator()(size_type hash) const;
+ };
+
+#include <ext/pb_ds/detail/hash_fn/direct_mask_range_hashing_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+#define PB_DS_CLASS_T_DEC template<typename Size_Type>
+#define PB_DS_CLASS_C_DEC direct_mod_range_hashing<Size_Type>
+
+ /// A mod range-hashing class (uses the modulo function).
+ template<typename Size_Type = std::size_t>
+ class direct_mod_range_hashing
+ : public detail::mod_based_range_hashing<Size_Type>
+ {
+ public:
+ typedef Size_Type size_type;
+
+ void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ protected:
+ void
+ notify_resized(size_type size);
+
+ /// Transforms the __hash value hash into a ranged-hash value
+ /// (using a modulo operation).
+ inline size_type
+ operator()(size_type hash) const;
+
+ private:
+ typedef detail::mod_based_range_hashing<size_type> mod_based_base;
+ };
+
+#include <ext/pb_ds/detail/hash_fn/direct_mod_range_hashing_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+#define PB_DS_CLASS_T_DEC template<bool External_Load_Access, typename Size_Type>
+#define PB_DS_CLASS_C_DEC hash_load_check_resize_trigger<External_Load_Access, Size_Type>
+#define PB_DS_SIZE_BASE_C_DEC detail::hash_load_check_resize_trigger_size_base<Size_Type, External_Load_Access>
+
+ /// A resize trigger policy based on a load check. It keeps the
+ /// load factor between some load factors load_min and load_max.
+ template<bool External_Load_Access = false, typename Size_Type = std::size_t>
+ class hash_load_check_resize_trigger : private PB_DS_SIZE_BASE_C_DEC
+ {
+ public:
+ typedef Size_Type size_type;
+
+ enum
+ {
+ /// Specifies whether the load factor can be accessed
+ /// externally. The two options have different trade-offs in
+ /// terms of flexibility, genericity, and encapsulation.
+ external_load_access = External_Load_Access
+ };
+
+ /// Default constructor, or constructor taking load_min and
+ /// load_max load factors between which this policy will keep the
+ /// actual load.
+ hash_load_check_resize_trigger(float load_min = 0.125,
+ float load_max = 0.5);
+
+ void
+ swap(hash_load_check_resize_trigger& other);
+
+ virtual
+ ~hash_load_check_resize_trigger();
+
+ /// Returns a pair of the minimal and maximal loads, respectively.
+ inline std::pair<float, float>
+ get_loads() const;
+
+ /// Sets the loads through a pair of the minimal and maximal
+ /// loads, respectively.
+ void
+ set_loads(std::pair<float, float> load_pair);
+
+ protected:
+ inline void
+ notify_insert_search_start();
+
+ inline void
+ notify_insert_search_collision();
+
+ inline void
+ notify_insert_search_end();
+
+ inline void
+ notify_find_search_start();
+
+ inline void
+ notify_find_search_collision();
+
+ inline void
+ notify_find_search_end();
+
+ inline void
+ notify_erase_search_start();
+
+ inline void
+ notify_erase_search_collision();
+
+ inline void
+ notify_erase_search_end();
+
+ /// Notifies an element was inserted. The total number of entries
+ /// in the table is num_entries.
+ inline void
+ notify_inserted(size_type num_entries);
+
+ inline void
+ notify_erased(size_type num_entries);
+
+ /// Notifies the table was cleared.
+ void
+ notify_cleared();
+
+ /// Notifies the table was resized as a result of this object's
+ /// signifying that a resize is needed.
+ void
+ notify_resized(size_type new_size);
+
+ void
+ notify_externally_resized(size_type new_size);
+
+ inline bool
+ is_resize_needed() const;
+
+ inline bool
+ is_grow_needed(size_type size, size_type num_entries) const;
+
+ private:
+ virtual void
+ do_resize(size_type new_size);
+
+ typedef PB_DS_SIZE_BASE_C_DEC size_base;
+
+#ifdef _GLIBCXX_DEBUG
+ void
+ assert_valid(const char* file, int line) const;
+#endif
+
+ float m_load_min;
+ float m_load_max;
+ size_type m_next_shrink_size;
+ size_type m_next_grow_size;
+ bool m_resize_needed;
+ };
+
+#include <ext/pb_ds/detail/resize_policy/hash_load_check_resize_trigger_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+#undef PB_DS_SIZE_BASE_C_DEC
+
+#define PB_DS_CLASS_T_DEC template<bool External_Load_Access, typename Size_Type>
+#define PB_DS_CLASS_C_DEC cc_hash_max_collision_check_resize_trigger<External_Load_Access, Size_Type>
+
+ /// A resize trigger policy based on collision checks. It keeps the
+ /// simulated load factor lower than some given load factor.
+ template<bool External_Load_Access = false, typename Size_Type = std::size_t>
+ class cc_hash_max_collision_check_resize_trigger
+ {
+ public:
+ typedef Size_Type size_type;
+
+ enum
+ {
+ /// Specifies whether the load factor can be accessed
+ /// externally. The two options have different trade-offs in
+ /// terms of flexibility, genericity, and encapsulation.
+ external_load_access = External_Load_Access
+ };
+
+ /// Default constructor, or constructor taking load, a __load
+ /// factor which it will attempt to maintain.
+ cc_hash_max_collision_check_resize_trigger(float load = 0.5);
+
+ void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ /// Returns the current load.
+ inline float
+ get_load() const;
+
+ /// Sets the load; does not resize the container.
+ void
+ set_load(float load);
+
+ protected:
+ /// Notifies an insert search started.
+ inline void
+ notify_insert_search_start();
+
+ /// Notifies a search encountered a collision.
+ inline void
+ notify_insert_search_collision();
+
+ /// Notifies a search ended.
+ inline void
+ notify_insert_search_end();
+
+ /// Notifies a find search started.
+ inline void
+ notify_find_search_start();
+
+ /// Notifies a search encountered a collision.
+ inline void
+ notify_find_search_collision();
+
+ /// Notifies a search ended.
+ inline void
+ notify_find_search_end();
+
+ /// Notifies an erase search started.
+ inline void
+ notify_erase_search_start();
+
+ /// Notifies a search encountered a collision.
+ inline void
+ notify_erase_search_collision();
+
+ /// Notifies a search ended.
+ inline void
+ notify_erase_search_end();
+
+ /// Notifies an element was inserted.
+ inline void
+ notify_inserted(size_type num_entries);
+
+ /// Notifies an element was erased.
+ inline void
+ notify_erased(size_type num_entries);
+
+ /// Notifies the table was cleared.
+ void
+ notify_cleared();
+
+ /// Notifies the table was resized as a result of this object's
+ /// signifying that a resize is needed.
+ void
+ notify_resized(size_type new_size);
+
+ /// Notifies the table was resized externally.
+ void
+ notify_externally_resized(size_type new_size);
+
+ /// Queries whether a resize is needed.
+ inline bool
+ is_resize_needed() const;
+
+ /// Queries whether a grow is needed. This method is called only
+ /// if this object indicated is needed.
+ inline bool
+ is_grow_needed(size_type size, size_type num_entries) const;
+
+ private:
+ void
+ calc_max_num_coll();
+
+ inline void
+ calc_resize_needed();
+
+ float m_load;
+ size_type m_size;
+ size_type m_num_col;
+ size_type m_max_col;
+ bool m_resize_needed;
+ };
+
+#include <ext/pb_ds/detail/resize_policy/cc_hash_max_collision_check_resize_trigger_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+#define PB_DS_CLASS_T_DEC template<typename Size_Type>
+#define PB_DS_CLASS_C_DEC hash_exponential_size_policy<Size_Type>
+
+ /// A size policy whose sequence of sizes form an exponential
+ /// sequence (typically powers of 2.
+ template<typename Size_Type = std::size_t>
+ class hash_exponential_size_policy
+ {
+ public:
+ typedef Size_Type size_type;
+
+ /// Default constructor, or onstructor taking a start_size, or
+ /// constructor taking a start size and grow_factor. The policy
+ /// will use the sequence of sizes start_size, start_size*
+ /// grow_factor, start_size* grow_factor^2, ...
+ hash_exponential_size_policy(size_type start_size = 8,
+ size_type grow_factor = 2);
+
+ void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ protected:
+ size_type
+ get_nearest_larger_size(size_type size) const;
+
+ size_type
+ get_nearest_smaller_size(size_type size) const;
+
+ private:
+ size_type m_start_size;
+ size_type m_grow_factor;
+ };
+
+#include <ext/pb_ds/detail/resize_policy/hash_exponential_size_policy_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+#define PB_DS_CLASS_T_DEC
+#define PB_DS_CLASS_C_DEC hash_prime_size_policy
+
+ /// A size policy whose sequence of sizes form a nearly-exponential
+ /// sequence of primes.
+ class hash_prime_size_policy
+ {
+ public:
+ /// Size type.
+ typedef std::size_t size_type;
+
+ /// Default constructor, or onstructor taking a start_size The
+ /// policy will use the sequence of sizes approximately
+ /// start_size, start_size* 2, start_size* 2^2, ...
+ hash_prime_size_policy(size_type start_size = 8);
+
+ inline void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ protected:
+ size_type
+ get_nearest_larger_size(size_type size) const;
+
+ size_type
+ get_nearest_smaller_size(size_type size) const;
+
+ private:
+ size_type m_start_size;
+ };
+
+#include <ext/pb_ds/detail/resize_policy/hash_prime_size_policy_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+#define PB_DS_CLASS_T_DEC template<typename Size_Policy, typename Trigger_Policy, bool External_Size_Access, typename Size_Type>
+
+#define PB_DS_CLASS_C_DEC hash_standard_resize_policy<Size_Policy, Trigger_Policy, External_Size_Access, Size_Type>
+
+ /// A resize policy which delegates operations to size and trigger policies.
+ template<typename Size_Policy = hash_exponential_size_policy<>,
+ typename Trigger_Policy = hash_load_check_resize_trigger<>,
+ bool External_Size_Access = false,
+ typename Size_Type = std::size_t>
+ class hash_standard_resize_policy
+ : public Size_Policy, public Trigger_Policy
+ {
+ public:
+ typedef Size_Type size_type;
+ typedef Trigger_Policy trigger_policy;
+ typedef Size_Policy size_policy;
+
+ enum
+ {
+ external_size_access = External_Size_Access
+ };
+
+ /// Default constructor.
+ hash_standard_resize_policy();
+
+ /// constructor taking some policies r_size_policy will be copied
+ /// by the Size_Policy object of this object.
+ hash_standard_resize_policy(const Size_Policy& r_size_policy);
+
+ /// constructor taking some policies. r_size_policy will be
+ /// copied by the Size_Policy object of this
+ /// object. r_trigger_policy will be copied by the Trigger_Policy
+ /// object of this object.
+ hash_standard_resize_policy(const Size_Policy& r_size_policy,
+ const Trigger_Policy& r_trigger_policy);
+
+ virtual
+ ~hash_standard_resize_policy();
+
+ inline void
+ swap(PB_DS_CLASS_C_DEC& other);
+
+ /// Access to the Size_Policy object used.
+ Size_Policy&
+ get_size_policy();
+
+ /// Const access to the Size_Policy object used.
+ const Size_Policy&
+ get_size_policy() const;
+
+ /// Access to the Trigger_Policy object used.
+ Trigger_Policy&
+ get_trigger_policy();
+
+ /// Access to the Trigger_Policy object used.
+ const Trigger_Policy&
+ get_trigger_policy() const;
+
+ /// Returns the actual size of the container.
+ inline size_type
+ get_actual_size() const;
+
+ /// Resizes the container to suggested_new_size, a suggested size
+ /// (the actual size will be determined by the Size_Policy
+ /// object).
+ void
+ resize(size_type suggested_new_size);
+
+ protected:
+ inline void
+ notify_insert_search_start();
+
+ inline void
+ notify_insert_search_collision();
+
+ inline void
+ notify_insert_search_end();
+
+ inline void
+ notify_find_search_start();
+
+ inline void
+ notify_find_search_collision();
+
+ inline void
+ notify_find_search_end();
+
+ inline void
+ notify_erase_search_start();
+
+ inline void
+ notify_erase_search_collision();
+
+ inline void
+ notify_erase_search_end();
+
+ inline void
+ notify_inserted(size_type num_e);
+
+ inline void
+ notify_erased(size_type num_e);
+
+ void
+ notify_cleared();
+
+ void
+ notify_resized(size_type new_size);
+
+ inline bool
+ is_resize_needed() const;
+
+ /// Queries what the new size should be, when the container is
+ /// resized naturally. The current __size of the container is
+ /// size, and the number of used entries within the container is
+ /// num_used_e.
+ size_type
+ get_new_size(size_type size, size_type num_used_e) const;
+
+ private:
+ /// Resizes to new_size.
+ virtual void
+ do_resize(size_type new_size);
+
+ typedef Trigger_Policy trigger_policy_base;
+
+ typedef Size_Policy size_policy_base;
+
+ size_type m_size;
+ };
+
+#include <ext/pb_ds/detail/resize_policy/hash_standard_resize_policy_imp.hpp>
+
+#undef PB_DS_CLASS_T_DEC
+#undef PB_DS_CLASS_C_DEC
+
+} // namespace __gnu_pbds
+
+#endif
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