class of vector ???

[sharris]

Hello everybody !

I been trying for hours to figure out how to use countLine in this code. It's a vector class and it use the raw pointers technique which is all new to me. For a simple vector I can use this:

cout << v_DATA.size();

... but nothing I tried worked in this class of vector. Could someone show me how to get the lineCount (Element Count) to work. Thanks in advance.

Source found here: c++ - How to write the content of different files to a vector for further use with getline - Stack Overflow

//  ...   You can use a class which handles some raw pointers (For Large Files)

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


class file_vector 
{
public:
  file_vector()
  {}

  virtual ~file_vector()
  {
    for( std::vector< std::ifstream* >::iterator it = 
                    m_file_streams.begin(); it != m_file_streams.begin(); it++)
    {
      std::ifstream * p_stream = *it;
      delete p_stream;
    }
  }

  void append_file(const std::string& file_name)
  {
    std::ifstream * p_stream = new std::ifstream( file_name.c_str() );
    if(p_stream->is_open())
      m_file_streams.push_back(p_stream);
    else
      delete p_stream;
  }

  void reset()
  {
    for( std::vector< std::ifstream* >::iterator it = 
                      m_file_streams.begin(); it != m_file_streams.end(); it++)
    {
      std::ifstream * p_stream = *it;
      p_stream->seekg(0,p_stream->beg);
    }
  }

  size_t size()
  {
    return m_file_streams.size();
  }

  std::ifstream & get(size_t index)
  {
    return * m_file_streams.at(index); // Using at because of index check
  }

  std::ifstream & operator [] (size_t index)
  {
    return get(index);
  }

private:
  std::vector< std::ifstream* > m_file_streams;
};


int main()
{
  file_vector files_content;
  files_content.append_file("file1.txt");
  files_content.append_file("file2.txt");
  files_content.append_file("file3.txt");

  for(size_t i = 0; i < files_content.size(); i++)
  {
    std::string current_line;
    while(std::getline(files_content[i],current_line))
      std::cout << current_line << std::endl;
  }

  files_content.reset(); // To make getline usable again


 cin.get();
 	return 0;
}

[laserlight]

What is countLine?

[sharris]

//  Make a file name "file1.txt" and add a few lines in it.
//  Save the file and run this program.  I just call it count lines
//  C++ people say counts elements.
//  This set-up give you a full string in one line, so make a few extra line.
//  It should work, if not let me know.  Thank you

#include <fstream>
#include <iostream>
#include <string>
#include <vector>

using namespace std;

int main()
{
 vector<string> v_DATA;
 string line;

 ifstream in("file1.txt");

    while (getline( in, line, '\n' ))
        {
          v_DATA.push_back( line );
        }
            sort( v_DATA.begin(), v_DATA.end() );
            for(int i = 0; i < v_DATA.size(); ++i)
            cout << v_DATA[i] <<  "\n";  

 cout << "\n\n";
 cout<<v_DATA.size(); // count Lines - - Show the number of lines in the file.

in.close();

 cin.get();
 	return 0;
}

[laserlight]

Sorry, I really don't understand what you are having problems with. You provided your file_vector class with a size() member function, so just use that. I don't see a problem (other than certain potential problems with your file_vector class, e.g., you should disable the copy constructor and copy assignment operator, and it is not clear why you want the class to be a base class when there are no virtual member functions besides the destructor).

[sharris]

Sorry, I really don't understand what you are having problems with. You provided your file_vector class with a size() member function member function, so just use that

I am not an expert like some of you may have became overnight and I did not completely understand the pointer/reference thing after completing a single c++ textbook among seven other class textbooks that needed my attention also. My instructors told me it could take years to master C++ or did he lie to me? If I knew how to work inside class vector build on pointers I would not have wrote two pages here asking for help. I'm sure you and everyone else knows that once I find or is shown the point of entry there is not a darn thing I cannot do afterward. Can you show me, in code, how to achieve what I am after? Just one line of code (or my own line posted above) and where to place it. sharris was not build in a day, I mean Rome'.

[whiteflags]

Ignoring all the whining: Counting the lines of one file should not be different from counting the lines of N files (even if you store streams in a file_vector class). Counting the lines of many files together implies that you need to loop the code that reads the file and counts said lines. That's it.

[sharris]

So, where do the loop go? Starting tomorrow I will but right now I don't have the smarts or the strength to step through the code to find that location, but I know for sure if I did I would have my TRUE working bucketSorter inserted before morning. I must of wanted it too bad. After more than ten hours of praying for an direct answer here and fifteen hours of coding and writing this 1000 word thread, i give up. I need sleep. I'll find my own answers. You guys have a nice day.

[Elysia]

In cases like these, you simply need to take a step back and think about the logic.
Logic should tell us that to count the lines of all files, we should do something like:
For every file
Count lines of file
Repeat

And how do we count the lines of a single file?
And please fix the indentation.

[sharris]

Logic, I can't take it. I need a debugger so I can see logic and action, that way I'll know for sure. You guy got debugger in your heads and I am not going out like that ... My dream to talk the talk so I can walk the walk is over ... I rather CODE, learn from examples, and get answers in code and not logic, unless it super simple.

Today, after I wake up, I will find the tools I need. I just been too excited and in a rush. I can't wait but I'm ok now. This way I don't have to ask questions.

And please fix the indentation.

Well at lease I use

 cin.get();
 	return 0; :)

Anyway, it be back in order soon.

Thanks


Btw: I always wanted a reason to work with pointer and this file was where I plan to start injecting my code so I can learn more. It was my gift from the other C++ gods