Thanks everybody for the detailed help.

Especially LanX' version is great, basically 6 lines of codes are doing the job and validating the input at the same time.

Thanks a lot!!!

Just one more question:

Is it possible to combine different types of rules in this algorithm? 

A not after B"
B after C

[download]
Thanks
Axel

In reply to Re^2: Sorting by dependencies by Anonymous Monk
in thread Sorting by dependencies by Anonymous Monk

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