Question

 #include<iostream>

using namespace std;

int main () 

{

    int x;
    cout << "Pls. enter a natural number" << "\n" ;
    cin >> x ;
     cout  << "\n" ;
    for (int i=1 ; i<=x ; i++ )
    {
        x = x-1;
        cout << i << " " << x << "\n" ;
    }
    cout  << "\n" ;
    system ("pause");
    return 0;
} $

I have this sample code with cin first then cout.. my problem is that instead of the cout to output in the cmd it will be sent to a .txt file.. Where will I include the fstream codes.. thanks a lot…

Answer 1

Use <fstream>:

#include <fstream>

// ...

std::ofstream ofs("output.txt");

ofs << "You said, " << n << "\n";

If you factor your printing code out, you can use either files or iostreams:

void print(std::ostream & o, int n) { o << "You said, " << n << "\n"; }

int main()
{
    int n = 11;
    std::ofstream ofs("output.txt");

    print(std::cout, n);
    print(ofs, n);
}