Confusing Algorithm

[Oscar Benjamin]

On 22 April 2013 13:56, Chris Angelico <rosuav at gmail.com> wrote:
> On Mon, Apr 22, 2013 at 10:39 PM, RBotha <r at ymond.co.za> wrote:
>> I'm facing the following problem:
>>
>> """
>> In a city of towerblocks, Spiderman can
>> “cover” all the towers by connecting the
>> first tower with a spider-thread to the top
>> of a later tower and then to a next tower
>> and then to yet another tower until he
>> reaches the end of the city. Threads are
>> straight lines and cannot intersect towers.
>> Your task is to write a program that finds
>> the minimal number of threads to cover all
>> the towers. The list of towers is given as a
>> list of single digits indicating their height.
>>
>> -Example:
>> List of towers: 1 5 3 7 2 5 2
>> Output: 4
>> """
>>
>> I'm not sure how a 'towerblock' could be defined. How square does a shape have to be to qualify as a towerblock? Any help on solving this problem?
>
> First start by clarifying the problem. My reading of this is that
> Spiderman iterates over the towers, connecting his thread from one to
> the next, but only so long as the towers get shorter:
>
>>-Example:
>>List of towers: 1 5 3 7 2 5 2
>>Output: 4
>
> First thread
> 1
> New thread
> 5-3
> New thread
> 7-2
> New thread
> 5-2
>
> There are other possible readings of the problem.

I read it differently. I thought the threads would go 1->5->7->5->2.


Oscar