cpp-search-server | rating

#include <algorithm>
#include <cmath>
#include <iostream>
#include <numeric>
#include <map>
#include <set>
#include <string>
#include <utility>
#include <vector>

using namespace std;

const int MAX_RESULT_DOCUMENT_COUNT = 5;

struct Document {
    int id;
    double relevance;
    int rating;
};

struct Query {
    set<string> words_;
    set<string> minus_words_;
};

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

int ReadLineWithNumber() {
    int result = 0;
    cin >> result;
    ReadLine();
    return result;
}

vector<int> ReadRatings(){
    int n;
    cin >> n;
    vector<int> ratings(n);
    for (int i = 0; i < n; ++i){
        cin >> ratings[i];
    }
    return ratings;
}


vector<int> ReadRatings2(){
    vector<int> ratings(ReadLineWithNumber());
    for (size_t i = 0; i < ratings.size(); ++i){
        cin >> ratings[i];
    }
    return ratings;
}

vector<string> SplitIntoWords(const string& text) {
    vector<string> words;
    string word;
    for (const char c : text) {
        if (c == ' ') {
            if (!word.empty()) {
                words.push_back(word);
                word.clear();
            }
        } else {
            word += c;
        }
    }
    if (!word.empty()) {
        words.push_back(word);
    }

    return words;
}

Query ParseQuery(const string& text) {
    Query query;
    string word;
    bool minus_word = false;
    for (const char c : text) {
        if (c == ' ') {
            if (!word.empty()) {
                if (minus_word){
                    query.minus_words_.insert(word);
                    minus_word = false;
                }
                else
                    query.words_.insert(word);
                word.clear();
            }
        }
        else if (c == '-') {
            minus_word = true;
        }
        else {
            word += c;
        }
    }
    if (!word.empty()) {
        if (minus_word)
            query.minus_words_.insert(word);
        else
            query.words_.insert(word);
    }

    return query;
    }

int ComputeAverageRating(const vector<int>& ratings) {
    return accumulate(ratings.begin(), ratings.end(), 0) / static_cast<int>(ratings.size());
}


class SearchServer {
private:
    struct DocumentContent {
        int id = 0;
        vector<string> words;
        int rating;
    };

    set<string> stop_words_;
    vector<DocumentContent> documents_;
    map<string, map<int, double>> word_to_document_freqs_;
    map<int, int> ratings_;

    vector<string> SplitIntoWordsNoStop(const string& text) const {
        vector<string> words;
        for (const string& word : SplitIntoWords(text)) {
            if (stop_words_.count(word) == 0) {
                words.push_back(word);
            }
        }
        return words;
    }

    double Compute_IDF(const string& word) const {
        return log( static_cast<double>(documents_.size())
            / static_cast<double>(word_to_document_freqs_.at(word).size()) );
    }

    void ExcludeMinusWords(const Query& query, map<int, double>& docs_relevance) const {
        for (const string& word : query.minus_words_){
            if (word_to_document_freqs_.count(word)){
                for (const auto& [id, tf] : word_to_document_freqs_.at(word)){
                    docs_relevance.erase(id);
                }
            }
        }
    }

    vector<Document> FindAllMatchedDocuments(const Query& query) const {
        map<int, double> docs_relevance;
        vector<Document> matched_documents;
        for (const string& word : query.words_){
            if (word_to_document_freqs_.count(word)){
                const double idf = Compute_IDF(word);
                for (const auto& [id, tf] : word_to_document_freqs_.at(word)){
                    docs_relevance[id] += idf * tf;
                }
            }
        }
        ExcludeMinusWords(query, docs_relevance);
        for (const auto& [id, relevance] : docs_relevance){
            matched_documents.push_back({id, relevance, ratings_.at(id)});
        }
        return matched_documents;
    }

public:

    void SetStopWords(const string& text){
        for (const string& word : SplitIntoWords(text)) {
            stop_words_.insert(word);
        }
    }

    void AddDocument(int document_id, const string& document, const vector<int>& ratings){
        const vector<string> words = SplitIntoWordsNoStop(document);
        int rating = ComputeAverageRating(ratings);
        double tf = 1. / words.size();
        for (const string& word : words){
            word_to_document_freqs_[word][document_id] += tf;
        }
        ratings_[document_id] = rating;
        documents_.push_back({document_id, words, rating});
    }

    vector<Document> FindTopDocuments(const string& raw_query) const {
        Query query = ParseQuery(raw_query);
        vector<Document> matched_documents = FindAllMatchedDocuments(query);
        sort(matched_documents.begin(), matched_documents.end(),
                [](const Document& ld, const Document& rd) {
                    return ld.relevance > rd.relevance;
                }
            );
        if (matched_documents.size() > MAX_RESULT_DOCUMENT_COUNT) {
            matched_documents.resize(MAX_RESULT_DOCUMENT_COUNT);
        }

        return matched_documents;
    }
};


SearchServer CreateSearchServer(){
    SearchServer search_server;
    //cout << "Set stop words:" << endl;
    search_server.SetStopWords(ReadLine());
    //cout << "Set amoumt of documents:" << endl;
    const int document_count = ReadLineWithNumber();
    for (int document_id = 0; document_id < document_count; ++document_id) {
        string words = ReadLine();
        vector<int> ratings = ReadRatings();
        search_server.AddDocument(document_id, words, ratings);
    }
    return search_server;
}

int main() {

    const SearchServer search_server = CreateSearchServer();
    for (auto [document_id, relevance, rating] : search_server.FindTopDocuments(ReadLine())) {
        cout << "{ document_id = "s << document_id << ", relevance = "s << relevance
             << ", rating = "s << rating << " }"s << endl;
    }

}