Advanced Control Flow

Processing Text Input

When processing text input, is the input structured as a sequence of characters, words, or lines?

To input a sequence of word, use the loop

string word;
while (cin >> word)
{
   process word
}

cin >> word has the same value as cin - it is the same test as !cin.fail().

To process input one line at a time, use the getline function.

string line;
while (getline(cin, line))
{
   process line
}

As above, the getline function returns cin, so you can test that cin hasn't yet failed.

To process input character by character, use the loop

char ch;
while (cin.get(ch))
{
   process ch
}