Спринт 9. Параллелим методы поисковой системы. Задание 3.

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main.cpp
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#include "process_queries.h"
#include "search_server.h"

#include <execution>
#include <iostream>
#include <random>
#include <string>
#include <vector>

#include "log_duration.h"

using namespace std;

string GenerateWord(mt19937& generator, int max_length) {
    const int length = uniform_int_distribution(1, max_length)(generator);
    string word;
    word.reserve(length);
    for (int i = 0; i < length; ++i) {
        word.push_back(uniform_int_distribution('a', 'z')(generator));
    }
    return word;
}

vector<string> GenerateDictionary(mt19937& generator, int word_count, int max_length) {
    vector<string> words;
    words.reserve(word_count);
    for (int i = 0; i < word_count; ++i) {
        words.push_back(GenerateWord(generator, max_length));
    }
    sort(words.begin(), words.end());
    words.erase(unique(words.begin(), words.end()), words.end());
    return words;
}

string GenerateQuery(mt19937& generator, const vector<string>& dictionary, int word_count, double minus_prob = 0) {
    string query;
    for (int i = 0; i < word_count; ++i) {
        if (!query.empty()) {
            query.push_back(' ');
        }
        if (uniform_real_distribution<>(0, 1)(generator) < minus_prob) {
            query.push_back('-');
        }
        query += dictionary[uniform_int_distribution<int>(0, dictionary.size() - 1)(generator)];
    }
    return query;
}

vector<string> GenerateQueries(mt19937& generator, const vector<string>& dictionary, int query_count, int max_word_count) {
    vector<string> queries;
    queries.reserve(query_count);
    for (int i = 0; i < query_count; ++i) {
        queries.push_back(GenerateQuery(generator, dictionary, max_word_count));
    }
    return queries;
}

template <typename ExecutionPolicy>
void Test(string_view mark, SearchServer search_server, const string& query, ExecutionPolicy&& policy) {
    LOG_DURATION(mark);
    const int document_count = search_server.GetDocumentCount();
    int word_count = 0;
    for (int id = 0; id < document_count; ++id) {
        const auto [words, status] = search_server.MatchDocument(policy, query, id);
        word_count += words.size();
    }
    cout << word_count << endl;
}

#define TEST(policy) Test(#policy, search_server, query, execution::policy)

int main() {
    mt19937 generator;

    const auto dictionary = GenerateDictionary(generator, 1000, 10);
    const auto documents = GenerateQueries(generator, dictionary, 10'000, 70);

    const string query = GenerateQuery(generator, dictionary, 500, 0.1);

    SearchServer search_server(dictionary[0]);
    for (size_t i = 0; i < documents.size(); ++i) {
        search_server.AddDocument(i, documents[i], DocumentStatus::ACTUAL, {1, 2, 3});
    }

    TEST(seq);
    TEST(par);
}
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document.cpp
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empty

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document.h
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#pragma once
#include <iostream>

struct Document {
    Document() = default;
    Document(int id, double relevance, int rating)
        : id(id)
        , relevance(relevance)
        , rating(rating) {
    }
    int id = 0;
    double relevance = 0.0;
    int rating = 0;
};

enum class DocumentStatus {
    ACTUAL,
    IRRELEVANT,
    BANNED,
    REMOVED,
};
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paginator.h
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#pragma once
#include <algorithm>
#include <vector>
#include <cassert>
#include <iostream>
#include "document.h"

using namespace std::string_literals;

template <typename IteratorRanges>
class IteratorRange {
public:
    explicit IteratorRange(IteratorRanges begin, IteratorRanges end) : begin_(begin),
                                                                       end_(end),
                                                                       size_(distance(begin, end)){}

    IteratorRanges begin() const  {
        return begin_;
    }

    IteratorRanges end() const {
        return end_;
    }

    size_t size() const {
        return size_;
    }

private:
    IteratorRanges begin_;
    IteratorRanges end_;
    size_t size_;
};

std::ostream& operator<<(std::ostream& out, const Document& document) {
    out << "{ document_id = "s << document.id
        << ", relevance = "s << document.relevance
        << ", rating = "s << document.rating << " }"s;
    return out;
}

template <typename To_Out>
std::ostream& operator<<(std::ostream& out, const IteratorRange<To_Out>& sheet) {
    auto helper = sheet.begin();
    while(helper != sheet.end()) {
        out<< *helper;
        ++helper;
    }
    return out;
}

template <typename Paginatorr>
class Paginator {
public :
    Paginator(const Paginatorr& result_begin, const Paginatorr& result_end, size_t size_of_sheet) {

        auto full_size = distance(result_begin, result_end);
        Paginatorr helper = result_begin;

        for (auto i = 0; i < full_size/size_of_sheet; ++i) {
            sheets.push_back(IteratorRange<Paginatorr>(helper, helper+ size_of_sheet));
            helper=helper+size_of_sheet;
        }

        if (helper!= result_end) {
            sheets.push_back(IteratorRange<Paginatorr>(helper, result_end));
        }
    }

    auto begin() const {
        return sheets.begin();
    }

    auto end() const {
        return sheets.end();
    }

    size_t size() {
        return sheets.size();
    }

private:
    std::vector<IteratorRange<Paginatorr>> sheets;
};

template <typename Container>
auto Paginate(const Container& c, size_t page_size) {
    return Paginator(begin(c),
                     end(c),
                     page_size);
}
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process_queries.cpp
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#include <execution>
#include <algorithm>
#include <list>

#include "process_queries.h"

std::vector<std::vector<Document>> ProcessQueries(const SearchServer& search_server,
                                                  const std::vector<std::string>& queries) {
    std::vector<std::vector<Document>> helper(queries.size());
    std::transform(std::execution::par,
                   queries.begin(),
                   queries.end(),
                   helper.begin(),
                   [&search_server](auto query){
                        return search_server.FindTopDocuments(query);
                   });
    return helper;
}

std::vector<Document> ProcessQueriesJoined(const SearchServer& search_server,
                                           const std::vector<std::string>& queries) {
    return std::transform_reduce(std::execution::par,
                                 queries.begin(),
                                 queries.end(),
                                 std::vector<Document>{},
                                 [](std::vector<Document> lhs, std::vector<Document> const& rhs){
                                     lhs.insert(lhs.end(), rhs.begin(), rhs.end());
                                     return lhs;
                                 },
                                 [&search_server](auto query){
                                     return search_server.FindTopDocuments(query);
                                 });
}
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process_queries.h
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#pragma once
#include "search_server.h"
#include <vector>
#include <string>

std::vector<std::vector<Document>> ProcessQueries(const SearchServer& search_server,
    const std::vector<std::string>& queries);

std::vector<Document> ProcessQueriesJoined(const SearchServer& search_server,
    const std::vector<std::string>& queries);
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read_input_functions.cpp
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#include "read_input_functions.h"
#include <iostream>

using namespace std::string_literals;

std::string ReadLine() {
    std::string s;
    std::getline(std::cin, s);
    return s;
}

int ReadLineWithNumber() {
    int result;
    std::cin >> result;
    ReadLine();
    return result;
}
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read_input_functions.h
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#pragma once
#include "document.h"
#include <string>

std::string ReadLine();
int ReadLineWithNumber();
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request_queue.cpp
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#include "request_queue.h"

std::vector<Document> RequestQueue::AddFindRequest(std::string_view raw_query,
                                                   DocumentStatus status) {
    return AddFindRequest(raw_query,
                          [&status](int document_id,
                                    DocumentStatus document_status,
                                    int rating) {
                                        return document_status == status;
                                    });
}

std::vector<Document> RequestQueue::AddFindRequest(std::string_view raw_query) {

    return AddFindRequest(raw_query,
                          DocumentStatus::ACTUAL);
}

int RequestQueue::GetNoResultRequests() const {
    return count_if(requests_.begin(),
                    requests_.end(),
                    [](QueryResult query) {
                        return query.query_result == 0;
                    });
}
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request_queue.h
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#pragma once
#include "search_server.h"
#include <deque>

class RequestQueue {
public:
    RequestQueue(const SearchServer& search_server) : search_request(search_server){}

    template <typename DocumentPredicate>
    std::vector<Document> AddFindRequest(std::string_view raw_query, DocumentPredicate document_predicate);
    std::vector<Document> AddFindRequest(std::string_view raw_query, DocumentStatus status);
    std::vector<Document> AddFindRequest(std::string_view raw_query);

    int GetNoResultRequests() const;
private:
    struct QueryResult {
        bool query_result;
    };

    const SearchServer& search_request;
    std::deque<QueryResult> requests_;
    const static int min_in_day_ = 1440;
};

template <typename DocumentPredicate>
std::vector<Document> RequestQueue::AddFindRequest(std::string_view raw_query,
                                                   DocumentPredicate document_predicate) {
    std::vector<Document> helper = search_request.FindTopDocuments(raw_query,
                                                                   document_predicate);
    QueryResult query;
    query.query_result = (helper.empty()==false);

    if (!(requests_.size() < min_in_day_)){
        requests_.pop_front();
    }

    requests_.push_back(query);
    return helper;
}
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search_server.cpp
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#include <numeric>
#include "search_server.h"

void SearchServer::AddDocument(int document_id,
                               std::string_view document,
                               DocumentStatus status,
                               const std::vector<int>& ratings) {

    if ((document_id < 0) || (documents_.count(document_id) > 0)) {
        throw std::invalid_argument("Invalid document ID"s);
    }

    auto [doc_id_, doc_data_] = documents_.emplace(document_id,
                                                   DocumentData{
                                                       std::string(document),
                                                       ComputeAverageRating(ratings),
                                                       status
                                                    });
    document_ids_.push_back(document_id);

    const auto words = SplitIntoWordsNoStop(doc_id_->second.data_string_);

    const double inv_word_count = 1.0 / words.size();

    for (auto word : words) {
        word_to_document_freqs_[word][document_id] += inv_word_count;
        ids_of_docs_to_word_freqs_[document_id][word] += inv_word_count;
    }
}

std::vector<Document> SearchServer::FindTopDocuments(std::string_view raw_query,
                                                     DocumentStatus status) const {
    return FindTopDocuments(raw_query,
                            [status](int document_id,
                                     DocumentStatus document_status,
                                     int rating) {
                                         return document_status == status;
                                     }
                           );
}

std::vector<Document> SearchServer::FindTopDocuments(std::string_view raw_query) const {
    return FindTopDocuments(raw_query,
                            DocumentStatus::ACTUAL);
}

int SearchServer::GetDocumentCount() const {
    return documents_.size();
}

std::vector<int>::const_iterator SearchServer::begin() const {
    return document_ids_.begin();
}

std::vector<int>::const_iterator SearchServer::end() const {
    return document_ids_.end();
}

const std::map<std::string_view, double>& SearchServer::GetWordFrequencies(int document_id) const {
    static const std::map<std::string_view, double> emptyes;
    return (!ids_of_docs_to_word_freqs_.count(document_id))
            ? emptyes
            : ids_of_docs_to_word_freqs_.at(document_id);
}

void SearchServer::RemoveDocument(int document_id) {
    RemoveDocument(std::execution::seq,
                   document_id);
}

void SearchServer::RemoveDocument(const std::execution::sequenced_policy&,
                                  int document_id) {
    auto helper = std::find(
                            document_ids_.begin(),
                            document_ids_.end(),
                            document_id);

    if (helper == document_ids_.end()) {
        return;
    } else {
        document_ids_.erase(helper);
    }

    documents_.erase(document_id);

    std::for_each(word_to_document_freqs_.begin(),
                  word_to_document_freqs_.end(),
                  [&](auto& helper) {
                      helper.second.erase(document_id);
                  });
}

void SearchServer::RemoveDocument(const std::execution::parallel_policy&,
                                  int document_id) {
    auto helper = std::find(std::execution::par,
                            document_ids_.begin(),
                            document_ids_.end(),
                            document_id);

    if (helper == document_ids_.end()) {
        return;
    } else {
        document_ids_.erase(helper);
    }

    documents_.erase(document_id);

    std::for_each(std::execution::par,
        word_to_document_freqs_.begin(),
                   word_to_document_freqs_.end(),
                   [&](auto& helper) {
                       helper.second.erase(document_id);
                   });
}

std::tuple<std::vector<std::string_view>, DocumentStatus> SearchServer::MatchDocument(std::string_view raw_query,
                                                                                      int document_id) const {
    return MatchDocument(std::execution::seq,
                         raw_query,
                         document_id);
}

std::tuple<std::vector<std::string_view>, DocumentStatus> SearchServer::MatchDocument(const std::execution::sequenced_policy&,
                                                                                      std::string_view raw_query,
                                                                                      int document_id) const {

    if ((document_id < 0) || (documents_.count(document_id) <= 0)) {
        throw std::invalid_argument("Non-existent document ID"s);
    }

    const auto result = ParseQuery(raw_query, std::execution::seq);
    std::vector<std::string_view> matched_words;

    for (auto word : result.minus_words) {
        if (word_to_document_freqs_.count(word) == 0) {
            continue;
        }
        if (word_to_document_freqs_.at(word).count(document_id)) {
            return {{}, documents_.at(document_id).status};
        }
    }

    for (auto word : result.plus_words) {
        if (word_to_document_freqs_.count(word) == 0) {
            continue;
        }
        if (word_to_document_freqs_.at(word).count(document_id)) {
            matched_words.push_back(word);
        }
    }

    return {matched_words,
            documents_.at(document_id).status};
}

std::tuple<std::vector<std::string_view>, DocumentStatus> SearchServer::MatchDocument(const std::execution::parallel_policy&,
                                                                                      std::string_view raw_query,
                                                                                      int document_id) const {

    if ((document_id < 0) || (documents_.count(document_id) <= 0)) {
        throw std::invalid_argument("Non-existent document ID"s);
    }

    const auto& result = ParseQuery(raw_query);

    const auto& checker = [this, document_id](std::string_view word) {
        const auto helper = word_to_document_freqs_.find(word);
        return helper!= word_to_document_freqs_.end() &&
                        helper->second.count(document_id);
    };

    if (std::any_of(std::execution::par,
                    result.minus_words.begin(),
                    result.minus_words.end(),
                    checker)) {
        return {{}, documents_.at(document_id).status};
    }

    std::vector<std::string_view> matched_words(result.plus_words.size());

    auto end = std::copy_if(std::execution::par,
                            result.plus_words.begin(),
                            result.plus_words.end(),
                            matched_words.begin(),
                            checker);

    std::sort(matched_words.begin(), end);
    end = std::unique(std::execution::par,
                      matched_words.begin(),
                      end);

    matched_words.erase(end, matched_words.end());
    return {matched_words,
            documents_.at(document_id).status};
}

bool SearchServer::IsStopWord(std::string_view word) const {
    return stop_words_.count(word) > 0;
}

bool SearchServer::IsValidWord(std::string_view word) {
    return std::none_of(word.begin(),
                        word.end(),
                        [](char c) {
                            return c >= '\0' && c < ' ';
                        }
    );
}

std::vector<std::string_view> SearchServer::SplitIntoWordsNoStop(std::string_view text) const {
    std::vector<std::string_view> words;

    for (std::string_view& word : SplitIntoWords(text)) {
        if (!IsValidWord(word)) {
            throw std::invalid_argument("Word "s + std::string(word) + " is invalid"s);
        }
        if (!IsStopWord(word)) {
            words.push_back(word);
        }
    }
    return words;
}

int SearchServer::ComputeAverageRating(const std::vector<int>& ratings) {
    if (ratings.empty()) {
        return 0;
    }
    int rating_sum = std::accumulate(ratings.begin(),
                                     ratings.end(),
                                     0);
    return rating_sum /static_cast<int>(ratings.size());
}

SearchServer::QueryWord SearchServer::ParseQueryWord(std::string_view& text) const {
    if (text.empty()) {
        throw std::invalid_argument("Query word is empty"s);
    }

    bool is_minus = false;

    if (text[0] == '-') {
        is_minus = true;
        text = text.substr(1);
    }

    if (text.empty() || text[0] == '-' || !IsValidWord(text)) {
        throw std::invalid_argument("Query word "s + std::string(text) + " is invalid");
    }
    return {text, is_minus, IsStopWord(text)};
}

SearchServer::Query SearchServer::ParseQuery(std::string_view& text) const {
    Query result;
    for (std::string_view& word : SplitIntoWords(text)) {
        const auto query_word = ParseQueryWord(word);
        if (!query_word.is_stop) {
            if (query_word.is_minus) {
                result.minus_words.push_back(query_word.data);
            } else {
                result.plus_words.push_back(query_word.data);
            }
        }
    }
    return result;
}

SearchServer::Query SearchServer::ParseQuery(std::string_view& text, const std::execution::sequenced_policy&) const {
    Query result;
    result = ParseQuery(text);

    std::sort(std::execution::par,
              result.minus_words.begin(),
              result.minus_words.end());
    std::sort(std::execution::par,
              result.plus_words.begin(),
              result.plus_words.end());

    result.minus_words.erase(std::unique(result.minus_words.begin(),
                                         result.minus_words.end()),
                             result.minus_words.end());
    result.plus_words.erase(std::unique(result.plus_words.begin(),
                                        result.plus_words.end()),
                            result.plus_words.end());

    return result;
}

double SearchServer::ComputeWordInverseDocumentFreq(std::string_view& word) const {
    return log(GetDocumentCount() * 1.0 / word_to_document_freqs_.at(word).size());
}
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search_server.h
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#pragma once
#include <tuple>
#include <algorithm>
#include <cmath>
#include <iostream>
#include <map>
#include <set>
#include <stdexcept>
#include <execution>
#include <string>
#include <vector>
#include "read_input_functions.h"
#include "string_processing.h"
#include "log_duration.h"

using namespace std::string_literals;

class SearchServer {
public:
    template <typename StringContainer>
    SearchServer(const StringContainer& stop_words);
    SearchServer(const std::string& stop_words_text) : SearchServer(SplitIntoWords(stop_words_text)){}
    SearchServer(std::string_view& stop_words_text) : SearchServer(SplitIntoWords(stop_words_text)){}
    SearchServer() = default;

    void AddDocument(int document_id,
                     std::string_view document,
                     DocumentStatus status,
                     const std::vector<int>& ratings);

    template <typename DocumentPredicate>
    std::vector<Document> FindTopDocuments(std::string_view raw_query,
                                           DocumentPredicate document_predicate) const;
    std::vector<Document> FindTopDocuments(std::string_view raw_query,
                                           DocumentStatus status) const;
    std::vector<Document> FindTopDocuments(std::string_view raw_query) const;

    int GetDocumentCount() const;

    std::vector<int>::const_iterator begin() const;
    std::vector<int>::const_iterator end() const;

    const std::map<std::string_view, double>& GetWordFrequencies(int document_id) const;

    void RemoveDocument(int document_id);
    void RemoveDocument(const std::execution::sequenced_policy&,
                        int document_id);
    void RemoveDocument(const std::execution::parallel_policy&,
                        int document_id);

    std::tuple<std::vector<std::string_view>, DocumentStatus> MatchDocument(std::string_view raw_query,
                                                                       int document_id) const;
    std::tuple<std::vector<std::string_view>, DocumentStatus> MatchDocument(const std::execution::sequenced_policy&,
                                                                       std::string_view raw_query,
                                                                       int document_id) const;
    std::tuple<std::vector<std::string_view>, DocumentStatus> MatchDocument(const std::execution::parallel_policy&,
                                                                       std::string_view raw_query,
                                                                       int document_id) const;

private:
    struct DocumentData {
        std::string data_string_;
        int rating;
        DocumentStatus status;
    };

    const double EPSILON = 1e-6;
    const int MAX_RESULT_DOCUMENT_COUNT = 5;

    const std::set<std::string, std::less<>> stop_words_;

    std::map<std::string_view, std::map<int, double>> word_to_document_freqs_;
    std::map<int, std::map<std::string_view, double>> ids_of_docs_to_word_freqs_;

    std::map<int, DocumentData> documents_;
    std::vector<int> document_ids_;

    bool IsStopWord(std::string_view word) const;
    static bool IsValidWord(std::string_view word);

    std::vector<std::string_view> SplitIntoWordsNoStop(std::string_view text) const;

    static int ComputeAverageRating(const std::vector<int>& ratings);

    struct QueryWord {
        std::string_view data;
        bool is_minus;
        bool is_stop;
    };

    QueryWord ParseQueryWord(std::string_view& text) const;

    struct Query {
        std::vector<std::string_view> plus_words;
        std::vector<std::string_view> minus_words;
    };

    Query ParseQuery(std::string_view& text) const;
    Query ParseQuery(std::string_view& text, const std::execution::sequenced_policy&) const;

    double ComputeWordInverseDocumentFreq(std::string_view& word) const;

    template <typename DocumentPredicate>
    std::vector<Document> FindAllDocuments(const Query& query,
                                           DocumentPredicate document_predicate) const;
};

template <typename StringContainer>
SearchServer::SearchServer(const StringContainer& stop_words) : stop_words_(MakeUniqueNonEmptyStrings(stop_words)){
    if (!all_of(stop_words_.begin(), stop_words_.end(), IsValidWord)) {
        throw std::invalid_argument("Some of stop words are invalid"s);
    }
}

template <typename DocumentPredicate>
std::vector<Document> SearchServer::FindTopDocuments(std::string_view raw_query,
                                                     DocumentPredicate document_predicate) const {
    const auto query = ParseQuery(raw_query, std::execution::seq);
    auto matched_documents = FindAllDocuments(query,
                                              document_predicate);

    sort(std::execution::par,
         matched_documents.begin(),
         matched_documents.end(),
         [this](const Document& lhs, const Document& rhs) {
             if (std::abs(lhs.relevance - rhs.relevance) < EPSILON) {
                 return lhs.rating > rhs.rating;
             } else {
                 return lhs.relevance > rhs.relevance;
             }
         });

    if (matched_documents.size() > MAX_RESULT_DOCUMENT_COUNT) {
        matched_documents.resize(MAX_RESULT_DOCUMENT_COUNT);
    }

    return matched_documents;
}

template <typename DocumentPredicate>
std::vector<Document> SearchServer::FindAllDocuments(const Query& query,
                                                     DocumentPredicate document_predicate) const {
    std::map<int, double> document_to_relevance;

    for (auto word : query.plus_words) {
        if (word_to_document_freqs_.count(word) == 0) {
            continue;
        }

        const double inverse_document_freq = ComputeWordInverseDocumentFreq(word);

        for (const auto [document_id, term_freq] : word_to_document_freqs_.at(word)) {
            const auto& document_data = documents_.at(document_id);

            if (document_predicate(document_id, document_data.status, document_data.rating)) {
                document_to_relevance[document_id] += term_freq * inverse_document_freq;
            }
        }
    }

    for (auto word : query.minus_words) {
        if (word_to_document_freqs_.count(word) == 0) {
            continue;
        }
        for (const auto [document_id, _] : word_to_document_freqs_.at(word)) {
            document_to_relevance.erase(document_id);
        }
    }

    std::vector<Document> matched_documents;

    for (const auto [document_id, relevance] : document_to_relevance) {
        matched_documents.push_back({document_id,
                                     relevance,
                                     documents_.at(document_id).rating
                                    });
    }

    return matched_documents;
}
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string_processing.cpp
-----------------------------------------------------------------------
#include "string_processing.h"

std::vector<std::string_view> SplitIntoWords(std::string_view text) {

    std::string_view delimiter = " ";
    std::vector<std::string_view> words;

    int64_t start_pos = text.find_first_not_of(delimiter);
    const int64_t end_pos = text.npos;

    while (start_pos != end_pos) {
        int64_t space = text.find(' ', start_pos);
        words.push_back(space == end_pos
                        ? text.substr(start_pos)
                        : text.substr(start_pos, space - start_pos));
        start_pos = text.find_first_not_of(delimiter, space);
    }

    return words;
}
-----------------------------------------------------------------------
string_processing.h
-----------------------------------------------------------------------
#pragma once
#include <set>
#include <vector>
#include <string>
#include <iostream>

std::vector<std::string_view> SplitIntoWords(const std::string_view text);

template <typename StringContainer>
std::set<std::string, std::less<>> MakeUniqueNonEmptyStrings(const StringContainer& strings) {
    std::set<std::string, std::less<>> non_empty_strings;
    std::string str_buf;
    for (auto& str : strings) {
        str_buf = str;
        if (!str_buf.empty()) {
            non_empty_strings.insert(str_buf);
        }
    }
    return non_empty_strings;
}
-----------------------------------------------------------------------
test_example_functions.cpp
-----------------------------------------------------------------------

empty

-----------------------------------------------------------------------
test_example_functions.h
-----------------------------------------------------------------------

empty