Reading from File to STL Queue

[simulationspecimen]

So I have an assignment to read data from a file into an STL queue. I know how to do push into the queue but I'm not sure how to do it from a file.

Can someone please provide me an example where you read into a queue from a file that contains integers.

Thanks in advance

[Ganado]

It's two different challenges, so separate out them in your mind.

The first challenge is given a file, can you read an integer out of it?
The second challenge is given an integer, can you push it into a queue?

It sounds like you know how to do the second challenge, so let's focus on the first one.

If your file is a sequence of space-separated integers, it's fairly easy, you just do something like:

std::ifstream fin("integers.txt");
int my_integer;
fin >> my_integer; // fills my_integer with a value. 

Now you have an integer in "my_integer" variable. Connect the the dots and add that integer to the queue.

[simulationspecimen]

Got it, thanks. So now the problem asks to do the same but with an input file that has both strings and integers.

Sample Input: 245 Geography

The thing I'm having trouble with is that I'm only allowed to use one queue

Here is the code i had for integers only.

int main()
{
    queue <int> a;

    ifstream inf("input.txt");
    ofstream outf("output.txt");

    if (inf)
    {
        int value;

        while (inf >> value)
        {
            a.push(value);
        }

    }

    outf << "Output: ";
    while (!a.empty())
    {
        outf << a.front() << ", ";
        a.pop();
    }

}

[JLBorges]

#include <iostream>
#include <string>
#include <utility>
#include <queue>
#include <fstream>

int main()
{
    std::ifstream in_file( "input.txt" ) ;

    // the queue contains pairs: each pair having an int and a string
    // https://en.cppreference.com/w/cpp/utility/pair
    std::queue< std::pair<int,std::string> > q ;

    int number ;
    std::string text ;
    while( in_file >> number >> text ) // for each pair read from the file
        q.emplace( number, text ) ; // place it into the queue (construct the pair in-situ)
        // https://en.cppreference.com/w/cpp/container/queue/emplace

    while( !q.empty() )
    {
        const auto& pair = q.front() ;
        std::cout << pair.first << ' ' << pair.second << '\n' ;

        /* or in C++17 (structured binding)
        const auto [ num, txt ] = q.front() ;
        std::cout << num << ' ' << txt << '\n' ;
        */  
        q.pop() ;
    }
}

[simulationspecimen]

Thank you, I changed some things but I got it. Thanks so much!