making an input file into a list

[paul314]

I have to sort an input file using lists. How do i make an input file into a list. Do i have to store it in a vector first?
The input file has 100 words in random order

#include <iostream>
#include <list>
#include <fstream> // ifstream and ofstream
#include <string> // string
#include <vector>  // For later, when you add a vector
#include <algorithm>

  // You may want to add this in later, when you add a vector so that you can use the sort in algorithm
void readFile(std::string, std::vector<std::string>, std::ifstream);
int main()
{
    std::list <int> data;
    std::string Input_File;
    std::string Output_File;
    std::vector<std::string> vectdata;
    std::string line;


    std::ifstream Num_Rec_File;
	std::ofstream Num_Rec_Output;

    std::cout << "Please enter the name of the input file";
	std::cin >> Input_File;

	std::cout << "\nPlease enter the name of the output file for these data:\n";
	std::cin >> Output_File;

	Num_Rec_File.open(Input_File);
	if (Num_Rec_File.fail())
	{
		std::cout << "\n" << Input_File << " was not able to be opened for reading\n";
		return 1;
	}
	else
	{
		std::cout << "\n" << Input_File << " was opened for reading\n";


	}

	Num_Rec_Output.open(Output_File);
	if (Num_Rec_Output.fail())
	{
		std::cout << "\n" << Output_File << " was not able to be opened for reading\n";
		return 1;
	}
	else
	{
		std::cout << "\n" << Output_File << " was opened for reading\n";
	}
//readFile(Input_File, vectdata, Num_Rec_File);
    std::list <int> alist;
	std::list <int>::iterator iter; //l_iter is the list iterator (basically an internal pointer)
	int ivalue;

	// Set l_iter to beginning
	iter = alist.begin();

	while (std::cin.good()) // changed loop slightly, will continue to go until non integer intered
	{
		alist.insert(iter, ivalue); // inserts at the beginning
		// Note that this also would work: alist.insert(alist.begin(), ivalue);
		//++iter; // This statement creates a run time error on some systems, as you advance the interator off the end of the list
		iter = alist.end();
		std::cin >> ivalue;
	}
	// sort the list
	alist.sort(); // This is a sort that is part of the list class.
	// print the list
	std::cout << "\nSorted list: \n";
	//for (iter = alist.begin(); iter != alist.end(); ++iter) - conventional for loop
	for (int i:alist) // Note that this range based for is new in C++11.  It won't work on the prior versions.
	{
		//std::cout << *iter << std::endl; // This uses the pointer to print the values in the list --- conventional loop
		std::cout << i << std::endl; // using the range based index
	}

	return 0;
}
  

[Thomas1965]

The input file has 100 words in random order

Your code doesn't match the description. If your input file has words why do you want to store ints ?
Anyway, to read and sort the words is actually very easy.

#include <iostream>
#include <fstream>
#include <string>
#include <list>

using namespace std;

int main() 
{
  list<string> words;
  ifstream src("your filename");
  string word;

  if (!src)
  {
    // handle error
  }
  while (src >> word)
  {
    words.push_back(word);
  }
  words.sort();
  // TO DO - use the sorted list
}

[paul314]

thanks thomas, Ya the whole list part was from an example from my teacher. I just didnt change anything yet. Thanks :)