Questions: If dataFs. isopen () returns false, then: - Output dataFileName, followed by ": error occurred while opening file" and a newline. - Terminate the program with the return value 1, so that the program does not proceed to read the file.

Solution Steps

The code attempts to open a file specified by the user. If the file fails to open, the program should print an error message including the filename and exit with a return code of 1. Currently, the code lacks error handling.

We need to check the result of dataFS.is_open() and perform the required actions if it returns false.

Insert the following code block immediately after line 12:

    if (!dataFS.is_open()) {
        cout << dataFileName << ": error occurred while opening file" << endl;
        return 1;
    }

Final Answer:

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

using namespace std;

int main() {
    ifstream dataFS;
    string dataFileName;
    int cradleQuantity;

    cin >> dataFileName;
    dataFS.open(dataFileName);

    if (!dataFS.is_open()) {
        cout << dataFileName << ": error occurred while opening file" << endl;
        return 1;
    }

    dataFS >> cradleQuantity;
    cout << cradleQuantity << endl;

    return 0;
}