Confusing Algorithm

[DJC]

On 22/04/13 13:39, RBotha 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?

It's not the algorithm that's confusing, it's the problem. First clarify 
the problem.
This appears to be a variation of the travelling-salesman problem. 
Except the position of the towers is not defined, only their height.
So either the necessary information is missing or whoever set the 
problem intended something else.