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opening file and putting into program

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Join Date: Sep 2008

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swbuko

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opening file and putting into program

Sep 17th, 2008

I'm writing a program that opens a file then sorts it a couple different ways then closes it. Someone in my class said something about using a getline function but I can't figure out how that works. I can't find a way to take a specific line in a text file and then put it into an array. How can I get each number into its own array?

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324 3211 223
233 4493 992

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Re: opening file and putting into program

Sep 17th, 2008

>>but I can't figure out how that works.

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <fstream>
#include <string>
using namespace std;
 
int main()
{
    ifstream in("filename.txt");
    string line;
    // read each line of the file
    while( getline( in, line) )
    {
          //blabla do something this line
    }
}
#include <fstream>
#include <string>
using namespace std;

int main()
{
    ifstream in("filename.txt");
    string line;
    // read each line of the file
    while( getline( in, line) )
    {
          //blabla do something this line
    }
}

>>I can't find a way to take a specific line in a text file
You have to read each line one at a time until you get to the line that you want.

>>How can I get each number into its own array?
What kind of array? int array?

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <fstream>
#include <string>
#include <vector>
using namespace std;
 
int main()
{
    vector<int> arry; // array of integers
    ifstream in("filename.txt");
    int num;
    // read each line of the file
    while( line >> num )
    {
          arry.push_back(num); // add the number to the array
    }
}
#include <fstream>
#include <string>
#include <vector>
using namespace std;

int main()
{
    vector<int> arry; // array of integers
    ifstream in("filename.txt");
    int num;
    // read each line of the file
    while( line >> num )
    {
          arry.push_back(num); // add the number to the array
    }
}