Question About Getline

Hi,

I've been programming some examples out of a book and I've noticed something about getline that's made me curious. In the following simple program, you enter a make and model of a car, and then it outputs it.

But say you change the line "cin.getline(make, 19);" to "cin.getline(make, 3);". Then, if you enter something like "ford" or anything longer than that, the program no longer asks you the second question. How come?

Code:

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#include <iostream>
using namespace std;

char model[20];
char make[20];

int main()
{
    cout << "Enter make: ";
    cin.getline(make, 19);
    cout << "Enter model: ";
    cin.getline(model, 19);

    cout << make << " " << model;
    return 0;
}

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Thanks.

Because there are still characters in the input buffer since the first cin.getline() call did not read everything. The characters that are left over get assigned to model.

Actually not. When the line is longer the stream goes into a failed state.

For this reason getline with C style strings is hard to use (I've never used it in practice). Use std::string, its version of getline and you won't have these worries:

Code:

---

#include <iostream>
#include <string>
using namespace std;


int main()
{
    string make, model;
    cout << "Enter make: ";
    getline(cin, make);
    cout << "Enter model: ";
    getline(cin, model);

    cout << make << " " << model;
    return 0;
}

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