\u81ea\u5df1\u5b9e\u73b0\u4e86\u4e00\u4e2a\u8df3\u8dc3\u8868\uff0c\u4e00\u5171\u4e09\u4e2a\u6587\u4ef6\uff0c\u4f7f\u7528\u7684\u662fc++\uff0c\u505a\u6210\u4e86\u6a21\u677f<\/p>\n
\u5f53\u7136\u53c2\u8003\u8fc7\u522b\u4eba\u7684\u4f5c\u54c1\u3002<\/p>\n
skipnode.h<\/p>\n
#ifndef SKIP_LIST_NODE_H_\r\n#define SKIP_LIST_NODE_H_\r\n\r\nnamespace skiplist {\r\n template<typename SortField, typename Value>\r\n class Node;\r\n\r\n template<typename SortField, typename Value>\r\n struct Level {\r\n Level() : forward(nullptr), span(0) {};\r\n\r\n Node<SortField, Value>* forward;\r\n int span;\t\/\/\u8de8\u5ea6\r\n };\r\n\r\n template<typename SortField, typename Value>\r\n class Node {\r\n public:\r\n Node(int node_level, const SortField& sort_field, const Value& value) \r\n : node_level_(node_level), sort_field_(sort_field), value_(value) {\r\n if (node_level_ > 0) {\r\n level_ = new Level<SortField, Value>[node_level_];\r\n }\r\n else {\r\n level_ = nullptr;\r\n }\r\n };\r\n\r\n ~Node() {\r\n if (level_ != nullptr)\r\n delete[] level_;\r\n };\r\n\r\n const Node<SortField, Value>* next() const {\r\n return level_[0].forward;\r\n };\r\n\r\n public:\r\n const SortField sort_field_;\r\n const Value value_;\r\n const int node_level_; \/\/\u4ece1\u5f00\u59cb\r\n Level<SortField, Value>* level_;\r\n };\r\n}\r\n\r\n#endif \/\/SKIP_LIST_NODE_H_\r\n<\/pre>\n <\/p>\n
random.h<\/p>\n
#ifndef SKIP_LIST_RANDOM_H_\r\n#define SKIP_LIST_RANDOM_H_\r\n#include <random>\r\n\r\nnamespace skiplist {\r\n class Random {\r\n public:\r\n template <class T>\r\n static T RandomInt(T low, T high) {\r\n static std::random_device rd;\r\n static std::default_random_engine engine(rd());\r\n\r\n std::uniform_int_distribution<T> dis(0, high - low);\r\n T dice_roll = dis(engine) + low;\r\n return dice_roll;\r\n }\r\n };\r\n}\r\n\r\n#endif \/\/SKIP_LIST_RANDOM_H_\r\n<\/pre>\n <\/p>\n
skiplist.h<\/p>\n
#ifndef SKIP_LIST_H_\r\n#define SKIP_LIST_H_\r\n\r\n#include <iostream>\r\n#include \"skipnode.h\"\r\n#include \"random.h\"\r\n\r\nnamespace skiplist {\r\n template<typename SortField, typename Value>\r\n class SkipList {\r\n public:\r\n SkipList() : max_level_(0), node_count_(0) {\r\n header_ = new Node<SortField, Value>(MAX_LEVEL, SortField(), Value());\r\n footer_ = new Node<SortField, Value>(0, SortField(), Value());\r\n for (int i = 0; i < MAX_LEVEL; i++) {\r\n header_->level_[i].forward = footer_;\r\n }\r\n };\r\n\r\n ~SkipList() { \r\n clear();\r\n delete header_;\r\n delete footer_;\r\n };\r\n\r\n const Node<SortField, Value>* find(const SortField& sort_field, int* rank = nullptr) const;\r\n const Node<SortField, Value>* at(int rank) const;\r\n const Node<SortField, Value>* back() const;\r\n bool insert(const SortField& sort_field, const Value& value);\r\n bool remove(const SortField& sort_field);\r\n\r\n int max_level() const { return max_level_; };\r\n int size() const { return node_count_; };\r\n\r\n \/\/\u6e05\u7a7a\u8df3\u8dc3\u8868\uff0c\u6ce8\u610f\u5934\u8282\u70b9\u548c\u5c3e\u8282\u70b9\u4f1a\u4fdd\u7559\r\n void clear() {\r\n Node<SortField, Value>* p = header_->level_[0].forward;\r\n while (p != footer_) {\r\n Node<SortField, Value>* q = p->level_[0].forward;\r\n delete p;\r\n p = q;\r\n }\r\n for (int i = 0; i < MAX_LEVEL; i++) {\r\n header_->level_[i].forward = footer_;\r\n header_->level_[i].span = 0;\r\n }\r\n node_count_ = 0;\r\n max_level_ = 0;\r\n }\r\n const Node<SortField, Value>* begin() const { return header_->level_[0].forward; }\r\n const Node<SortField, Value>* end() const { return footer_; }\r\n\r\n void DumpAllNodes() const;\r\n void DumpNodeDetail(const Node<SortField, Value>* node) const;\r\n\r\n private:\r\n Node<SortField, Value>* CreateNode(const SortField& sort_field, const Value& value) const {\r\n int nodeLevel = GetRandomLevel();\r\n if (node_count_ == 0) {\r\n nodeLevel = 1;\r\n } else if (nodeLevel > max_level_) {\r\n nodeLevel = max_level_ + 1;\r\n }\r\n\r\n Node<SortField, Value>* node = new Node<SortField, Value>(nodeLevel, sort_field, value);\r\n return node;\r\n }\r\n\r\n \/\/\u968f\u673a\u751f\u6210\u4e00\u4e2alevel\r\n static int GetRandomLevel() {\r\n int level = 1;\r\n while (level < MAX_LEVEL && Random::RandomInt(0, 1) == 0) {\r\n level++;\r\n }\r\n\r\n return level;\r\n }\r\n\r\n private:\r\n int max_level_;\t\t\t\t\t\t\/\/\u4ece1\u5f00\u59cb\r\n int node_count_;\t\t\t\t\t\/\/\u8282\u70b9\u6570\u91cf\uff0c\u4e0d\u5305\u62ec\u5934\u8282\u70b9\u548c\u5c3e\u8282\u70b9\r\n Node<SortField, Value>* header_;\r\n Node<SortField, Value>* footer_;\r\n\r\n static const int MAX_LEVEL = 24;\t\/\/\u6700\u591a\u652f\u63011000\u4e07\u7684\u6570\u636e\u91cf\r\n };\r\n\r\n template<typename SortField, typename Value>\r\n const Node<SortField, Value>* SkipList<SortField, Value>::find(const SortField& sort_field, int* rank) const {\r\n if (rank != nullptr) {\r\n *rank = 1;\r\n }\r\n\r\n Node<SortField, Value>* node = header_;\r\n for (int i = max_level_ - 1; i >= 0; --i) {\r\n \/\/\u627e\u5230\u76ee\u6807\u8282\u70b9\u7684\u524d\u8282\u70b9\r\n while (node->level_[i].forward != footer_ && node->level_[i].forward->sort_field_ < sort_field) {\r\n if (rank != nullptr) *rank += node->level_[i].span;\r\n node = node->level_[i].forward;\r\n }\r\n }\r\n\r\n \/\/\u5982\u679c\u8be5\u8df3\u8dc3\u8868\u4e3a\u7a7a\uff0c\u5934\u8282\u70b9\u5c31\u4f1a\u76f4\u63a5\u6307\u5411\u5c3e\u8282\u70b9\r\n if (node == footer_)\r\n return nullptr;\r\n\r\n node = node->level_[0].forward;\r\n if (node == footer_)\r\n return nullptr;\r\n if (node->sort_field_ != sort_field)\r\n return nullptr;\r\n return node;\r\n };\r\n\r\n \/\/\u83b7\u53d6\u6392\u884c\u699c\u7b2crank\u540d\uff0c\u4ece1\u5f00\u59cb\r\n template<typename SortField, typename Value>\r\n const Node<SortField, Value>* SkipList<SortField, Value>::at(int rank) const {\r\n int cur_rank = 0;\r\n Node<SortField, Value>* node = header_;\r\n for (int i = max_level_ - 1; i >= 0; --i) {\r\n \/\/\u627e\u5230\u76ee\u6807\u8282\u70b9\u7684\u524d\u8282\u70b9\r\n while (node->level_[i].forward != footer_ && cur_rank + node->level_[i].span < rank) {\r\n cur_rank += node->level_[i].span;\r\n node = node->level_[i].forward;\r\n }\r\n }\r\n\r\n \/\/\u5982\u679c\u8be5\u8df3\u8dc3\u8868\u4e3a\u7a7a\uff0c\u5934\u8282\u70b9\u5c31\u4f1a\u76f4\u63a5\u6307\u5411\u5c3e\u8282\u70b9\r\n if (node == footer_)\r\n return nullptr;\r\n\r\n cur_rank += node->level_[0].span;\r\n node = node->level_[0].forward;\r\n\r\n if (node == footer_)\r\n return nullptr;\r\n if (cur_rank != rank)\r\n return nullptr;\r\n return node;\r\n }\r\n\r\n \/\/\u83b7\u53d6\u6700\u540e\u4e00\u4e2a\u8282\u70b9\r\n template<typename SortField, typename Value>\r\n const Node<SortField, Value>* SkipList<SortField, Value>::back() const {\r\n Node<SortField, Value>* node = header_;\r\n for (int i = max_level_ - 1; i >= 0; --i) {\r\n while (node->level_[i].forward != footer_) {\r\n node = node->level_[i].forward;\r\n }\r\n }\r\n\r\n \/\/\u5982\u679c\u8be5\u8df3\u8dc3\u8868\u4e3a\u7a7a\uff0c\u5934\u7ed3\u70b9\u5c31\u4f1a\u76f4\u63a5\u6307\u5411\u5c3e\u8282\u70b9\uff0c\u6b64\u65f6\u6700\u540e\u4e00\u4e2a\u8282\u70b9\u4e3a\u7a7a\r\n if (node == footer_)\r\n return nullptr;\r\n return node;\r\n }\r\n\r\n template<typename SortField, typename Value>\r\n bool SkipList<SortField, Value>::insert(const SortField& sort_field, const Value& value) {\r\n Node<SortField, Value>* update[MAX_LEVEL];\r\n int rank[MAX_LEVEL];\r\n\r\n Node<SortField, Value>* node = header_;\r\n for (int i = max_level_ - 1; i >= 0; --i) {\r\n \/\/rank[i-1]\u7528\u6765\u8bb0\u5f55\u7b2ci\u5c42\u8fbe\u5230\u63d2\u5165\u4f4d\u7f6e\u7684\u6240\u8de8\u8d8a\u7684\u8282\u70b9\u603b\u6570,\u4e5f\u5c31\u662f\u8be5\u5c42\u6700\u63a5\u8fd1(\u5c0f\u4e8e)\u7ed9\u5b9ascore\u7684\u6392\u540d \r\n \/\/rank[i-1]\u521d\u59cb\u5316\u4e3a\u4e0a\u4e00\u5c42\u6240\u8de8\u8d8a\u7684\u8282\u70b9\u603b\u6570,\u56e0\u4e3a\u4e0a\u4e00\u5c42\u5df2\u7ecf\u52a0\u8fc7\r\n rank[i] = (i == (max_level_ - 1) ? 0 : rank[i+1]);\r\n\r\n while (node->level_[i].forward != footer_ && node->level_[i].forward->sort_field_ < sort_field) {\r\n rank[i] += node->level_[i].span;\r\n node = node->level_[i].forward;\r\n }\r\n update[i] = node;\r\n }\r\n\r\n node = node->level_[0].forward;\r\n\r\n \/\/\u5982\u679ckey\u5df2\u5b58\u5728\r\n if (node != footer_ && node->sort_field_ == sort_field) {\r\n return false;\r\n }\r\n\r\n \/\/\u521b\u5efa\u65b0\u8282\u70b9\r\n Node<SortField, Value>* newNode = CreateNode(sort_field, value);\r\n\r\n \/\/\u6bcf\u6b21\u6700\u591a\u589e\u52a0\u4e00\u5c42\r\n if (newNode->node_level_ > max_level_) {\r\n max_level_ = newNode->node_level_;\r\n rank[max_level_ - 1] = 0;\r\n update[max_level_ - 1] = header_;\r\n update[max_level_ - 1]->level_[max_level_ - 1].span = size();\r\n }\r\n\r\n \/\/\u8c03\u6574forward\u6307\u9488\r\n for (int i = 0; i < newNode->node_level_ ; ++i) {\r\n node = update[i];\r\n newNode->level_[i].forward = node->level_[i].forward;\r\n node->level_[i].forward = newNode;\r\n\r\n newNode->level_[i].span = node->level_[i].span - (rank[0] - rank[i]);\r\n node->level_[i].span = rank[0] - rank[i] + 1;\r\n }\r\n\r\n for (int i = max_level_ - 1; i >= newNode->node_level_; --i) {\r\n update[i]->level_[i].span++;\r\n }\r\n\r\n ++node_count_;\r\n return true;\r\n };\r\n\r\n template<typename SortField, typename Value>\r\n void SkipList<SortField, Value>::DumpAllNodes() const {\r\n for (const Node<SortField, Value>* itr = begin(); itr != end(); itr = itr->next()) {\r\n DumpNodeDetail(itr);\r\n std::cout << std::endl;\r\n }\r\n std::cout << std::endl;\r\n }\r\n\r\n template<typename SortField, typename Value>\r\n void SkipList<SortField, Value>::DumpNodeDetail(const Node<SortField, Value>* node) const {\r\n std::cout << \"level:\" << node->node_level_\r\n << \",sort:\" << node->sort_field_\r\n << \",value:\" << node->value_;\r\n int node_level = node->node_level_ > max_level_ ? max_level_ : node->node_level_;\r\n for (int i = 0; i <= node_level - 1; ++i) {\r\n std::cout << \",[forward:\" << i \r\n << \",span:\" << node->level_[i].span\r\n << \"]->\" << node->level_[i].forward->sort_field_;\r\n }\r\n std::cout << \" \";\r\n }\r\n\r\n template<typename SortField, typename Value>\r\n bool SkipList<SortField, Value>::remove(const SortField& sort_field) {\r\n \/\/\u4fdd\u5b58\u7684\u662f\u8981\u5220\u9664\u7684\u524d\u4e00\u4e2a\u8282\u70b9\r\n Node<SortField, Value>* update[MAX_LEVEL];\r\n Node<SortField, Value>* node = header_;\r\n for (int i = max_level_ - 1; i >= 0; --i) {\r\n while (node->level_[i].forward != footer_ && node->level_[i].forward->sort_field_ < sort_field) {\r\n node = node->level_[i].forward;\r\n }\r\n update[i] = node;\r\n }\r\n\r\n if (node == footer_)\r\n return false;\r\n\r\n node = node->level_[0].forward;\r\n if (node == footer_)\r\n return false;\r\n\r\n \/\/\u5982\u679c\u8282\u70b9\u4e0d\u5b58\u5728\r\n if (node->sort_field_ != sort_field) {\r\n return false;\r\n }\r\n\r\n \/\/\u73b0\u5728node\u5df2\u7ecf\u88ab\u627e\u5230\uff0c\u5c06\u8981\u88ab\u5220\u9664\uff0c\r\n for (int i = 0; i <= max_level_ - 1; ++i) {\r\n if (update[i]->level_[i].forward != node) {\r\n update[i]->level_[i].span--;\r\n } else {\r\n update[i]->level_[i].forward = node->level_[i].forward;\r\n update[i]->level_[i].span += (node->level_[i].span - 1);\r\n }\r\n }\r\n delete node;\r\n\r\n \/\/\u66f4\u65b0max_level_\u7684\u503c\uff0c\u56e0\u4e3a\u6709\u53ef\u80fd\u5728\u79fb\u9664\u4e00\u4e2a\u8282\u70b9\u4e4b\u540e\uff0cmax_level_\u503c\u4f1a\u53d1\u751f\u53d8\u5316\uff0c\u53ca\u65f6\u964d\u4f4e\u53ef\u63d0\u9ad8\u6027\u80fd\r\n while (max_level_ > 0 && header_->level_[max_level_ - 1].forward == footer_) {\r\n --max_level_;\r\n }\r\n\r\n --node_count_;\r\n return true;\r\n };\r\n}\r\n#endif \/\/SKIP_LIST_H_\r\n<\/pre>\n <\/p>\n","protected":false},"excerpt":{"rendered":"
\u81ea\u5df1\u5b9e\u73b0\u4e86\u4e00\u4e2a\u8df3\u8dc3\u8868\uff0c\u4e00\u5171\u4e09\u4e2a\u6587\u4ef6\uff0c\u4f7f\u7528<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[],"tags":[119],"class_list":["post-3638","post","type-post","status-publish","format-standard","hentry","tag-03-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/3638","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=3638"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/3638\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=3638"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=3638"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=3638"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}