factor/library/math/random.factor

! Copyright (C) 2003, 2005 Slava Pestov.
! See http://factor.sf.net/license.txt for BSD license.
IN: math USING: kernel ;

: (random-int-0) ( n bits val -- n )
    3dup - + 1 < [
        2drop (random-int) 2dup swap mod (random-int-0)
    ] [
        2nip
    ] ifte ; inline

: random-int-0 ( max -- n )
    1+ dup power-of-2? [
        (random-int) * -31 shift
    ] [
        (random-int) 2dup swap mod (random-int-0)
    ] ifte ; inline

: random-int ( min max -- n )
    dupd swap - random-int-0 + ; flushable