Basic List Question

Arrangements, sorting, packing, partitions, critical path analysis, networks, graphs, ...
Post Reply
PracticeProbs
Posts: 1
Joined: Sun Aug 25, 2013 4:17 pm

Basic List Question

Post by PracticeProbs » Sun Sep 08, 2013 2:18 pm

Hello everyone. So (full disclosure) my class's discrete structures teacher gave the class a riddle- find a list that contains a different number of prefixes than suffixes. Unfortunately, nobody is able to think of an example. It seems intuitive that every list of size n contains exactly n prefixes and n suffixes (or n + 1 if we include the empty set), and I cannot think of a single list that this isn't true for. Any ideas?

Much appreciated.

thundre
Posts: 356
Joined: Sun Mar 27, 2011 9:01 am

Re: Basic List Question

Post by thundre » Wed Sep 11, 2013 11:58 am

I suppose you have the answer by now.

I suspect that it depends on some nuance of the definition of "list" you're using in that class. Your analysis sounds correct to me, FWIW.
Image

Post Reply