Running through exclusive sets (maths problem, not sure how to solve)

I need to run through every conbination of 10 items - say A-J

so ABCDEFGHIJ is posible and so is BADECGFIHJ

but AAAAAAAAA is not or even AABCDEFGHI

theres proberley a simple loop soultion, but its evading me atm

http://www.codeguru.com/forum/printt...hreadid=224458

If Blobby's reference doesn't do it for you, try this.