(Corresponds to Section 4.3 of ANSI X3.9-1978 FORTRAN 77.)

An integer constant also may have one of the following forms:

B'binary-digits' O'octal-digits' Z'hexadecimal-digits' X'hexadecimal-digits'

`binary-digits`, `octal-digits`, and `hexadecimal-digits`
are nonempty strings of characters in the set `01`

, `01234567`

,
and `0123456789ABCDEFabcdef`

, respectively.
(The value for `A`

(and `a`

) is 10, for `B`

and `b`

is 11, and so on.)