C++ 在.txt文件中查找顶级字数-而循环速度非常慢且无法正常工作

我正在尝试迭代.txt文件中的每个单词，当我发现一个单词（从我的单词映射中）包含超过maxwordcount变量时，我将其添加到topwords向量的前面

int main(int argc, char** argv) {
    fstream txtfile;
    string filename = argv[1];
    string word, tempword;
    int maxwordcount = 0;
    int wordcount = 0;
    int uniquewordcount = 0;
    vector<pair <string, int> > topwords;
    map<string, int> words;

if (argc != 2) {
    cout << "Incorrect number of arguments on the command line bud" << endl;
}else{
    txtfile.open(filename.c_str());
if (txtfile.is_open()) {
        while (txtfile >> word){
            //removePunctuation(word);
            //transform(word.begin(), word.end(), word.begin(), [](unsigned char c){ return::tolower(c); });     //makes string lowercase using iterator
            if (words.find(word) == words.end()) {   
                words[word] = 1;                                //adds word into the map as a pair starting with a word count of 1
                if (words[word] > maxwordcount) {            //For case if word is the first word added to the map
                    maxwordcount = words[word];              //change maxwordcount
                    topwords.insert( topwords.begin(), make_pair(word, words[word]) );    //insert word into the front of the top words vector
                    cout << "word: '" << word << "'  word-count: " << words[word] << endl;
                }
                uniquewordcount++;              
            }else{                                          //the word is found
                words[word]++;                              //increment count for word by 1
                if (words[word] > maxwordcount) {           //check if wordcount > maxwordcount
                    topwords.insert( topwords.begin(), make_pair(word, words[word]) );      //insert word into the front of the top words vector       
                }                                           
            }
            wordcount++;
        }

结果:

word: 'This'  word-count: 1
1
2
3
4
5
6
7
7
7
8
8
There were 11 words in the file.
There were 8 unique words in the file.
Top 20 words in little.txt:
   hey 2
   test 3
   test 2
   This 1
Segmentation fault

---

我知道我做错了什么，但我不知道下一步该去哪里或测试什么。在C++和C中也是业余爱好者。

你应该逐行读取文件，逐行处理< /p> 逐行读取文件：

---

这个问题很久以前就被问过了。我被这个问题绊倒了，asnwer和我发现一切都太复杂了

因此，我想添加一个更现代的C++解决方案，利用现有的STL元素。 这使得代码更加紧凑

请参阅下文：

#include <iostream>
#include <utility>
#include <unordered_map>
#include <vector>
#include <algorithm>
#include <string>
#include <fstream>

const std::string fileName{"r:\\loremipsum.txt"};

int main() {

    if (std::ifstream textFileStream{ fileName }; textFileStream) {

        // Here we store the count of all words
        std::unordered_map<std::string, size_t> counter{};

        size_t countOfOverallWords{}; // Counter for the number of all words

        // Read all words from file, remove punctuation, and count teh occurence
        for (std::string word; textFileStream >> word; counter[word]++) {
            word.erase(std::remove_if(word.begin(), word.end(), ispunct), word.end());
            ++countOfOverallWords;
        }
        // For storing the top 10
        std::vector<std::pair<std::string, size_t>> top(10);

        // Get top 10
        std::partial_sort_copy(counter.begin(), counter.end(), top.begin(), top.end(),
            [](const std::pair<std::string, size_t >& p1, const std::pair<std::string, size_t>& p2) { return p1.second > p2.second; });

        // Now show result
        std::cout << "Count of overall words:\t " << countOfOverallWords << "\nCount of unique words:\t " << counter.size() << "\n\nTop 10:\n";
        for (const auto& t : top) std::cout << "Value: " << t.first << "\t Count: " << t.second << '\n';
    }
    else std::cerr << "\n\nError: Could not open source file '" << fileName << "'\n\n";

    return 0;
}

#包括
#包括
#包括
#包括
#包括
#包括
#包括
常量std:：字符串文件名{“r:\\loremipsum.txt”}；
int main（）{
if（std:：ifstream textFileStream{fileName}；textFileStream）{
//这里我们存储所有单词的计数
std:：无序的_映射计数器{}；
size\u t countOfOverallWords{}；//所有字数的计数器
//从文件中读取所有单词，删除标点符号，并计算出现的次数
用于（std:：string word；textFileStream>>word；计数器[word]++）{
word.erase（std:：remove_if（word.begin（）、word.end（）、ispunt）、word.end（））；
++总字数；
}
//用于存储前10名
std：：向量top（10）；
//获得前10名
std：：部分排序拷贝（counter.begin（）、counter.end（）、top.begin（）、top.end（），
[]（const std:：pair&p1，const std:：pair&p2）{返回p1.second>p2.second；}）；
//现在显示结果
std：：您是否尝试使用较小的文件，例如5个单词？我认为您的算法不起作用：如果您的文件以100个单词“x”开头，并且没有其他单词重复100次，那么您的
topwords
将只包含对该单词“x”的引用。查找
max heap
此外，我假设我用于此的所有文本文件都是充满大量不同单词的书籍。程序员的秘密武器是调试器。有了调试器，你可以根据自己的条件运行程序，如果需要，一条指令一条指令地运行，并在运行时观察发生了什么。Typical用法是从粗略的步骤开始，查看程序执行意外操作的功能级别。当它执行时，您可能发现了一个bug，需要缩小范围。重新启动程序并前进到函数，这一步是进入函数。不断深入查看，直到您了解发生错误的事件顺序找到bug。然后砍掉它的头。尝试
无序映射
而不是
映射
。当你处理大量数据时，它会变得更快。我实际上有一个重复的项目，我在那里做这件事，但这让我很难不做一系列拆分就不断检查每个单词，等等。我告诉我们我建议使用算法库来实现这一点。但是看起来不错！<-----您可能会喜欢more中的第三个选项
#include <bits/stdc++.h>
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <string>
#include <algorithm>
#include <sstream>
#include <regex>
#include <iterator>

using namespace std;


vector<std::pair <string, int> > topwords;

void store(vector<pair <string, int> > &topwords, string str){
    auto pos = std::find_if(topwords.begin(), topwords.end(),
                            [str](std::pair<string, int> const &b) {
            return b.first == str;
});
    
    //std::cout<< pos->first << endl;
    
    if(pos != topwords.end()){
        std::cout << "word: " << pos->first << " " << pos->second << " found" << endl;
        pos->second++;
    }
    else{
        std::cout << "not found" << endl;
        topwords.push_back( make_pair(str,1) );
    }
}

void removeDupWord(string str)
{
    // Used to split string around spaces.
    istringstream ss(str);
    
    // Traverse through all words
    /*
    do {
        // Read a word
        string word;
        ss >> word;
        
        // Print the read word
        cout << word << endl;
        store(topwords, word );
        
        // While there is more to read
    } while (ss);
    */
    string word;
    while (ss >> word) {
        //cout << word << endl;
        const std::regex sanitized{ R"([-[\]{}()*+?.,\^$|#\s])" };
        
        std::stringstream result;
        std::regex_replace(std::ostream_iterator<char>(result), word.begin(), word.end(), sanitized, "");
        
        //store(topwords, word );
        store(topwords, result.str() );
    }
}

void readReadFile(string &fileName){
    std::cout << "fileName" << fileName << endl;
    std::ifstream file(fileName);
    std::string str;
    while (std::getline(file, str)) {
        //std::cout << str << "\n";
        removeDupWord(str);
        //store(topwords, str);
    }
}

bool compareFunction (const std::pair<std::string, int> &a, const std::pair<std::string, int> &b) {
    
    return a.first<b.first; // sort by letter
}

bool compareFunction2 (const std::pair<std::string, int> &a, const std::pair<std::string, int> &b) {
    
    return a.second>b.second; // sort by count
}

bool cmp(pair<string, int> &A, pair<string, int> &B) {
    return A.second < B.second;
}

void check(vector<pair <string, int> > &topwords){
    std::pair<string, int> mostUsedWord = make_pair("",0);
    for(auto ii : topwords){
        std::cout << "word: " << ii.first << " count: " << ii.second << endl;
        if(ii.second > mostUsedWord.second){
            mostUsedWord.first = ii.first;
            mostUsedWord.second = ii.second;
        }
    }
    std::cout << "most used Word: " << mostUsedWord.first << " x " << mostUsedWord.second << " Times." << endl;
           
}

void get_higestTopTenValues(vector<pair <string, int> > &topwords){
    std::sort(topwords.begin(),topwords.end(),compareFunction2);//sort the vector by count
    int MAX = std::max_element(topwords.begin(), topwords.end(), cmp)->second;
    std::cout << "max: " << MAX << endl;
    for(auto ii : topwords){
        //std::cout << "word: " << ii.first << " count: " << ii.second << endl;
        if(ii.second >= (MAX - 10)){
            std::cout << ii.first << " " << ii.second << endl;
            
        }
    }
}

void get_LowestTopTenValues(vector<pair <string, int> > &topwords){
    std::sort(topwords.begin(),topwords.end(),compareFunction2);//sort the vector by count
    int MIN = std::min_element(topwords.begin(), topwords.end(), cmp)->second;
    std::cout << "min: " << MIN << endl;
    for(auto ii : topwords){
        //std::cout << "word: " << ii.first << " count: " << ii.second << endl;
        if(ii.second <= (MIN + 9)){
            std::cout << ii.first << " " << ii.second << endl;
            
        }
    }
}

int main ()
{
    std::string word, fileName;
    
    fileName = "input.txt";
    readReadFile(fileName);
    
    topwords.push_back( make_pair("ba",1) );
    topwords.push_back( make_pair("bu",1) );
    topwords.push_back( make_pair("hmmm",1) );
    topwords.push_back( make_pair("what",1) );
    topwords.push_back( make_pair("and",1) );
    topwords.push_back( make_pair("hello",1) );
    
    word = "hellos";
    
    store(topwords, word);
    store(topwords, word);
    store(topwords, word);
    store(topwords, word);
    
    word = "hello";
    
    store(topwords, word);
    store(topwords, word);
    store(topwords, word);
    store(topwords, word);
    store(topwords, word);
    store(topwords, word);
    
    std::sort(topwords.begin(),topwords.end(),compareFunction);//sort the vector by letter
    // or
    //std::sort(topwords.begin(),topwords.end(),compareFunction2);//sort the vector by count
    
    
    std::cout << "---------------------------------------" << endl;
    std::cout << " get all values" << endl;
    std::cout << "---------------------------------------" << endl;
    check(topwords);
    
    
    std::cout << "---------------------------------------" << endl;
    std::cout << " get the top 10 highest values" << endl;
    std::cout << "---------------------------------------" << endl;
    get_higestTopTenValues(topwords);
    
    std::cout << "---------------------------------------" << endl;
    std::cout << " get the top 10 lowest values" << endl;
    std::cout << "---------------------------------------" << endl;
    get_LowestTopTenValues(topwords);
    
}

#include <iostream>
#include <utility>
#include <unordered_map>
#include <vector>
#include <algorithm>
#include <string>
#include <fstream>

const std::string fileName{"r:\\loremipsum.txt"};

int main() {

    if (std::ifstream textFileStream{ fileName }; textFileStream) {

        // Here we store the count of all words
        std::unordered_map<std::string, size_t> counter{};

        size_t countOfOverallWords{}; // Counter for the number of all words

        // Read all words from file, remove punctuation, and count teh occurence
        for (std::string word; textFileStream >> word; counter[word]++) {
            word.erase(std::remove_if(word.begin(), word.end(), ispunct), word.end());
            ++countOfOverallWords;
        }
        // For storing the top 10
        std::vector<std::pair<std::string, size_t>> top(10);

        // Get top 10
        std::partial_sort_copy(counter.begin(), counter.end(), top.begin(), top.end(),
            [](const std::pair<std::string, size_t >& p1, const std::pair<std::string, size_t>& p2) { return p1.second > p2.second; });

        // Now show result
        std::cout << "Count of overall words:\t " << countOfOverallWords << "\nCount of unique words:\t " << counter.size() << "\n\nTop 10:\n";
        for (const auto& t : top) std::cout << "Value: " << t.first << "\t Count: " << t.second << '\n';
    }
    else std::cerr << "\n\nError: Could not open source file '" << fileName << "'\n\n";

    return 0;
}