c++ - 解析第一行全部为 1's and second line all 2' 的文本文件

Question

我已经创建了一个程序，它将一个文件逐行读取一个文本文件，并将每行中的单个单词分开(用空格分隔)。现在我希望能够编辑代码，以便第一行的所有标记都为 1，第二行的所有标记都为 2如果有人可以帮助我，请下面是我的代码:

#include <iostream>
using std::cout;
using std::endl;

#include <fstream>
using std::ifstream;
#include <cmath>
#include <string>

const int MAX_CHARS_PER_LINE = 512;
const int MAX_TOKENS_PER_LINE = 20;
const char* const DELIMITER = " ";
using namespace std;
int main()
{
    string filename;
  // create a file-reading object
 /*std::ifstream file1("file1.txt", ios_base::app);
std::ifstream file2("file2.txt");

std::ofstream combinedfile("combinedfile.txt");
combinedfile << file1.rdbuf() << file2.rdbuf();*/

  ifstream fin;
  //enter in file name combinedfile.txt
  cout <<"please enter file name (including .txt)";
  cin >> filename ;
  fin.open(filename); // open a file
  if (!fin.good()) 
    return 1; // exit if file not found

  // read each line of the file
  while (!fin.eof())
  {
    // read an entire line into memory
    char buf[MAX_CHARS_PER_LINE];
    fin.getline(buf, MAX_CHARS_PER_LINE);

    // parse the line into blank-delimited tokens
    int n = 0; // a for-loop index

    // array to store memory addresses of the tokens in buf
    const char* token[MAX_TOKENS_PER_LINE] = {}; // initialize to 0

    // parse the line
    token[0] = strtok(buf, DELIMITER); // first token
    if (token[0]) // zero if line is blank
    {
      for (n = 1; n < MAX_TOKENS_PER_LINE; n++)
      {
        token[n] = strtok(0, DELIMITER); // subsequent tokens
        if (!token[n]) break; // no more tokens
      }
    }

    // process (print) the tokens
    for (int i = 0; i < n; i++) // n = #of tokens
      cout << "Token[" << i << "] = " << token[i] << endl;
    cout << endl;
  }
  system("pause");
  return 0;
}

所以输出应该是这样的:

Token[1] = This
Token[1] = course
Token[1] = provides
Token[1] = detailed
Token[1] = coverage
Token[1] = of
Token[1] = the
Token[1] = concepts
Token[1] = and
Token[1] = syntax

Token[2] = Coverage
Token[2] = includes
Token[2] = inheritance,
Token[2] = overloaded
Token[2] = operators,
Token[2] = overloaded
Token[2]= default
Token[2] = operators,

Answer 1

如果你只是想把单词分成两个容器，第一个包含第一行的单词，第二个包含第二行的单词，你可以使用 vector 来存储它们，并使用字符串流从一行中提取单词文字:

#include <sstream>
#include <string>
#include<vector>
#include<fstream>
using namespace std;

int main()
{
    ifstream infile("test.txt");
    string line;
    string word;
    vector< vector<string> >  tokens(2);
    for (int ix = 0; ix < 2; ++ix)
    {    
        getline(infile, line);
        istringstream iss(line);
        while(iss >> word)
            tokens[ix].push_back(word);
    }   
}

此处，tokens[0] 是包含第一行单词的 vector ，tokens[1] 包含第二行单词。