VB 6 - optimization/simplification of an array

First I want to apologize because my english.

I have an array of Nx2 with something like this:

A B
A C
A D
A F
B C
B D
B J
C D
C K

and I need to combine them to simplify all the coincidents, for example:

If exist A B , B C , C D , A C , A D , B C , B D then

A B C D (put the three together)


I can make it manually for a specific number of rows/inputs, but I don't know how do it for random number of entries.

Any ideas?