[OT] Destroying all human life on Earth AT THE SAME TIME

[Gregor Richards]

John Reimer wrote:
> Hello Gregor,
> 
>> You want to destroy all life on Earth. However, you don't want people
>> panicking as this could alter the result, so you want all humans to
>> die at the same instant. To do this, you're creating nano-robots. A
>> single nano-robot cannot control a persons mind: Seven are required
>> (three in each half of the brain and one in the brain stem).
>> Nano-robots can harvest material from their host to build new
>> nano-robots, but the host will die after approximately twenty
>> nano-robots-worth of material has been harvested (they require
>> particular rare particles that can only be harvested from the heart
>> and lungs). Nano-robots may communicate with one-another via
>> broadcast, but the range is limited to 1 mile. Nano-robots do not have
>> unique identification globally, but do have unique identification
>> within a body (that is, nano-robots in the same body can distinguish
>> each other, but broadcast messages from a nano-robot in one human
>> cannot implicitly be distinguished from broadcasts from another).
>> These broadcasts travel at the speed of light (seeing as that they are
>> light). Nano-robots harvest energy from their host, and as such can
>> survive indefinitely. A nano-robot in a dead host survives long enough
>> that this variable is not relevant for this problem.
>>
>> Robots can only be spread by direct physical contact from an infected
>> host to an uninfected one, and the process of transferring one
>> nano-robot destroys two nano-robots (that is, the infected host loses
>> three robots in the process but the new host only gains one).
>>
>> Devise an algorithm for these nano-robots that will destroy all human
>> life on Earth in a minimum amount of time, but with which all humans
>> will be destroyed within five minutes of each other. That is, minimize
>> the time from deploying the first nano-robot to the initial human life
>> being exterminated, and minimize the time from the initial human life
>> being exterminated to all human life being exterminated. You may
>> assume a maximum of twelve degrees of separation between average
>> industrialized people and that even the most remote tribe is connected
>> by at least one human to the industrialized world.
>>
>> Bonus: How would you change this algorithm if you wanted to destroy
>> all animal life? All life? How would you change it if astronauts were
>> considered?
>>
>> - Gregor Richards
>>
> 
> 
> Ok, Gregor.  I'll bite.  What's your fascination with this problem?  Are 
> you trying to make a point about something?
> 
> If "yes", you may as well be direct about it.  If "no", then why the 
> thread hijacking?  Come on... help me out... I'm a little slow 
> sometimes. :)
> -JJR
> 
> 

Thread hijacking? Seriously? This isn't a forum, there are totally 
disconnected subthreads within any thread.

This is what we call a "joke". On the one hand it's a parody of the 
always-annoying real-life-algorithm thread, on the other hand it's a 
parody of the needlessly-loaded choice of settings for the 
oh-didn't-I-mention-it's-always-annoying real-life-algorithm. This 
problem could be formalized as a simple tree-based message-passing 
communication problem, but instead we've gone political. Well, so long 
as war is involved, let's step it up and destroy everything. Yeeee haw.

  - Gregor Richards