Random number generation in LISP or using it

[bolega]

I am a newbie with the following problem.

A the outset let me state that the limitation is that I have to use
this inside emacs to scramble a set of chosen lines like you do
"reverse-region" or "sort-lines". It is possible that I can call some
scheme or clisp functions.

What is a fast(est) method to randomize lines based on the
capabilities of emacs ?

The function "random" does not work in emacs. I guess one get the
start line and end line of a marked region and then use that to
disorder (or re-order) the lines according to a list of random numbers
generated ?

1 -> 5
2 -> 8
3 -> 6
4 -> 9
5 -> 1
6 -> 3
7 -> 2
8 -> 7
9 -> 4

and then use these pairs to reorder the lines. I guess there is a need
for one or two variables to hold the lines, or just a kill or the top
line and go down a certain number of random steps and paste it there ?
Then come back to the top and do the same thing. The type of capacity
I am looking is to randomize about few hundred short lines of about 20
to 30 characters.

In this case one needs to generate a random number that is an integer
and lies between the lines start and end of region. It can be done by
some modulo type operation if available in emacs lisp.

Thanks for any help.
gnuist