[Typo3-dev] Splitting array acording to alphabet

[Georg Ringer]

Hello,

now I have really got a hard nut to crack:
I havw got a muldidimensional array which looks like this:
[count] [last name] [first name] [id] which is sorted by last name.

Now I want to show before every third alphabetic caracter a varible.
Example list:
Auerbach, Bloch, Brecht, Caspar, Frisch, Gabor, Gandhi, Hauschka, Hesse,
Kant, Lichtenberg, Loren, Marshall,.....

The result should be:
ABC: Auerbach, Bloch, Brecht, Caspar,
DEF: Frisch
GHI: Gabor, Gandhi, Hauschka, Hesse
JKL: Kant, Lichtenberg, Loren
MNO: Marshall

Can somebody please help me with this problem or can tell me how I can
resolve it?

many many thanks
Georg