关于C++文件的输出

// P 188
// outfile.cpp -- writing to a file
#include<iostream>
#include<fstream> // for file I/O

int main()
{
    using namespace std;
    
    char automobile[50];
    int year;
    double a_price;
    double d_price;
    
    ofstream outFile;   // create object
    outFile.open("carinfo.txt");// associate with a file
    
    cout << "Enter the make and model of automobile: ";
    cin.getline(automobile, 50);
    cout << "Enter the model year: ";
    cin >> year;
    cout << "Enter the original asking price: ";
    cin >> a_price;
    d_price = 0.913 * a_price;
    
// display information on screen with cout

    cout << fixed;
    cout.precision(2);
    cout.setf(ios_base::showpoint);
    cout << "Make and model: " << automobile << endl;
    cout << "Year: " << year << endl;
    cout << "Was asking $" << a_price << endl;
    cout << "Now asking $" << d_price << endl;
    
// now do exact same thing using outFile instead of cout

    outFile << fixed;
    outFile.precision(2);
    outFile.setf(ios_base::showpoint);
    outFile << "Make and model: " << automobile << endl;
    outFile << "Year: " << year << endl;
    outFile << "Was asking $" << a_price << endl;
    outFile << "Now asking $" << d_price << endl;
    
    outFile.close();
    return 0;
}