C++: exiting a for loop push_back command with a specific command

Question

I was learning to push_back vectors in C++, and I got to where I can use it. However, the code I made, pasted below, asks the user every time the loop ends if the user wants to continue the loop or not. I found this very inconvenient, so I wanted to change the code to where when the user inputs ("EXIT"), it would break the for loop. How would I have to change the code in this case? I pasted the whole code just in case I may have to change the portions besides the for loop.

#define all student_marks.begin(), student_marks.end()

using namespace std;

int main()
{
    vector<double> student_marks; //create container

    double mark;
    char more_students = 'y'; //set default to yes ('y')

    while (more_students=='y' || more_students=='Y') {
        cout<<"Enter mark for student #"<<student_marks.size()+1<<":";
        cin>>mark; //enter mark

        student_marks.push_back(mark); //push_back

        cout<<"More students?(y/n)";
        cin>>more_students; //user selects to break or continue the loop
    }

    double sum = accumulate(all, 0.0), average = sum/student_marks.size(); //sum and ave

    cout<<endl
    <<"Total mark:\t\t"<<sum<<endl
    <<"Average mark:\t"<<average<<endl
    <<"Highest mark:\t"<<*max_element(all)<<endl
    <<"Lowest mark:\t"<<*min_element(all)<<endl<<endl;

    cout<<"-----Score list-----"<<endl;
    sort(all,greater<double>()); //sort list

    for (size_t i=0; i<student_marks.size(); i++)
        cout<<"#"<<i+1<<". "<<student_marks[i]<<endl; //outputs results as list



    return 0;
}

Answer 1

You could just stay in the loop as long as the user inputs valid marks:

cout << "Enter mark for student #1:"

while(cin >> mark) {
    students_marks.push_bak(mark);
    cout << "Enter mark for student #" << marks.size() + 1;
}

The loop will exit as soon as the user enters something other than a double, e.g. the EOF flag.