c++ - 如何在 C++ 中将文本文件传输到二维数组？

Question

如何在 C++ 中将文本文件 (.txt) 传输到二维数组，这是我的源代码

fstream fin('textfile.txt', ios::in);
int matrix[n][m]; // n is the number of rows and m is the number of columns
for(int i = 0;i < n; i++){
     for(int j = 0; j<m; j++){
     fin>>matrix[i][j];
     }
}

但是我怎样才能确定 n 和 m 来做这件事，我需要你的帮助和建议，请加入我们你的观点

Answer 1

此解决方案需要 C++11+

如果文件中没有n&m，则必须假设布局也是二维的

One Two Three
Four Five Six

警告::未经测试的代码。

std::stringstream res;
std::string wordUp;
std::vector<std::string> str;

// the matrix, vector of vector of strings.
std::vector<std::vector<std::string>> matrix;  

fstream fin('textfile.txt', ios::in);
int lines = 0;
int words = 0;

// read the file line by line using `getline` 
for (std::string line; std::getline(fin, line); ) {
  ++lines;
  // use stringstream to count the number of words (m).
  res.str(line); // assign line to res. might also need some reset of good().
  while (res.good()) {
    res >> wordUp;
    str.push_back(wordUp);
    ++words;  
  }
  matrix.push_back(str);
  str.erase(str.begin());
}