Another possible solution to an NP-complete problem?

A couple of days ago a research team comprised of faculty at Nanyang Technological University in Singapore, the University of Southampton in the UK, and IQFR-CSIC in Madrid, Spain published a paper containing a creative solution to a problem known to be NP-complete, namely a version of the traveling salesman problem. The TSP, in summary, postulates a scenario in which you have an arbitrary number of towns spread over a large area and an arbitrary number of paths connecting them. What is the shortest possible path one can take in which the traveler visits each town only once and returns …

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Random knowledge VIII.

You're getting old if you consider sleeping until 0900 'sleeping in'.



When configuring a firewall with IPTables you have to specify the protocol before the port number(s) in each command. Do this:

iptables -A INPUT -s 1.2.3.4 -p tcp --dport 22 -j ACCEPT

and not this

iptables -A INPUT -s 1.2.3.4 --dport 22 -p tcp -j ACCEPT

If you don't, you'll see error messages to the effect of "Unknown arg '--dport'"

When writing Snort rules, there are a few things to keep in mind. First of all, rules come in two parts: the …

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