Therefore the regular expression A*B will match the strings AB, AAB, AAAB, or any other string starting with an A and ending with a single B.

The books' publisher, Bungeisha, says the series - one each for types b, o, a, and AB - has combined sales of well over 5 million copies.

For instance, the option string ab: indicates that the calling program knows two options: -a and -b, and that the next word after -b is a supplemental argument. Here's how the code looks.