[OT] Retreating from Iraq

[BCS]

Reply to KennyTM~,

> Andrei Alexandrescu wrote:
> 
>> Suppose that a miracle happen and the decision is taken at the
>> highest level to retreat all of US military presence from Iraq. That
>> will take a while, but sending the orders quickly is a must.
>> 
>> For utmost certainty, all orders are to be sent via phone and down
>> the command chain, and only to direct subordinates. Each officer has
>> a variable number of subordinates. Initially the president calls his
>> immediate subordinates, who call their immediate subordinates, etc.
>> Each call can be assumed to take the same amount of time.
>> 
>> Devise an algorithm that ensures every foot soldier gets the news as
>> quickly as possible, show it is correct, and show it is fast.
>> 
>> Andrei
>> 
> Hm, just call every subordinate you have? You need to tell everyone
> anyway.
> 
> I can't figure out the problem.
> 

who do you call first?