Re: problem with a reverse iterator

[brad]

Victor Bazarov wrote:

An element of a string is of type 'char'. As you have found out
already, the value is controlled by the encoding of the symbol.
If you want to convert a char that supposedly contains a decimal
digit into its corresponding number, you need to (a) test to see
that it's actually a digit (see 'isdigit' function) and (b) if it
is a digit, subtract '0' from it:
if (isdigit(*rit))
cout << position << (*rit - '0') * 2 << endl;
else
cerr << position << " - not a digit!!!" << endl;

> position++;
}
}

V

Wow. That works. I do not fully understand why it works, but I wanted to
thank you for the advice. I'll research it more until I better understand.

Brad

[Pete Becker]

On 2008-05-05 18:21:52 -0400, brad <by*******@gmail.comsaid:

>
Wow. That works. I do not fully understand why it works, but I wanted
to thank you for the advice. I'll research it more until I better
understand.

'0' is a character. It happens to also be a number, but it's the number
that represents the character '0' in whatever encoding the compiler
uses (typically ASCII). But C and C++ both have a rule that the
representations of the characters '0' through '9' must be contiguous
and increasing, that is, '1' is one more than '0', etc. So to convert a
character that represents a digit into the value of that digit, just
subtract '0'.

--
Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)