C++ ifstream 问题。我想从 a.csv 文件中读取“坐标”，但不知何故，代码读取了文件两次，并且输入了奇怪的数字

Question

I have a problem trying to read coordinates from a.csv file to a 2d array, to use it as input to a linear regression model.I know how to read from a file to an array but i needed the informations of the file to be double and not string so I thought i should see what the output whould be. I can't get it right.The problem is that the file's lines are being read 30 times each one of them and i can't figure it out. The code is here:

    #include <iostream>
    #include <fstream>
    #include <sstream>
    #include <string>
    #include <cmath>
    #include <limits>
    #include <iomanip>
    #include <vector>
    using namespace std;


    int main()
    {
           cout<<setprecision(10);
           //vector<vector<double> > observ_matr;
           ifstream myfile("Salary_Data.csv");
           vector<vector<double> > vec;
           string line;
           while(getline(myfile,line))
           {
                  stringstream lineStream(line);
                  string cell;
                  vector<double> temp_vec;
                  while(getline(lineStream, cell, ','))
                  {
                          temp_vec.push_back(atof(cell.c_str()));
                  }
                  vec.push_back(temp_vec);
           }
           for(int i=0;i<vec.size();i++)
           {
                  for(int j=0;j<vec.size();j++)
                  {
                          cout<<vec[i][j]<<"\t\t";
                  }
                  cout<<endl;
           }
           //cout<<vec[1].size();

           return 0;
     }

"myfile" is this, this.csv file

The output i am getting after running the code is this:

Answer 1

The problem is here...

    for (int j = 0; j < vec[i].size(); j++) // vec[i].size() instead of vec.size()