WORLD_VALUES = {:o => :water, :X => :land}
WORLD = [[:o,:o,:o,:o,:o,:o,:o,:o,:o,:o],
[:o,:o,:o,:o,:X,:X,:o,:o,:o,:o],
[:o,:o,:o,:o,:o,:o,:o,:o,:X,:X],
[:o,:o,:o,:X,:o,:o,:o,:o,:o,:X],
[:o,:o,:o,:X,:o,:X,:X,:o,:o,:o],
[:o,:o,:o,:o,:X,:X,:X,:X,:o,:o],
[:o,:o,:o,:X,:X,:X,:X,:X,:X,:X],
[:o,:o,:o,:X,:X,:o,:X,:X,:X,:o],
[:o,:o,:o,:o,:o,:o,:X,:X,:o,:o],
[:X,:X,:o,:o,:o,:X,:o,:o,:o,:o],
[:o,:o,:o,:o,:o,:o,:o,:o,:o,:o]]
def continent_size(x, y)
size = 0
begin
WORLD.first(x).each do |row|
row.first(y).each do |col|
size += 1 if WORLD_VALUES[col] == :land
end
end
rescue
return "invalid continent size"
end
return size
end
continent_size 10, 10 #should be 30
HTH,
Aldo Sarmiento
jordantheous wrote:
> *From Chris Pine, Learn to Program
>
> Hey All --
> In the below source code they array is called in the method as x, y,
> but the "if" statements are looking to [y][x]. Can anyone explain to
> me why they are switched? If you make them [x][y] it still outputs
> the correct number (23).
> Thanks in advance,
> Jordan
>
> ## Start of Example
>
> # These are just to make the map
> # easier for me to read. "M" is
> # visually more dense than "o".
>
> M = ' land '
> o = ' water '
> world = [[o,o,o,o,o,o,o,o,o,o,o],
> [o,o,o,o,M,M,o,o,o,o,o],
> [o,o,o,o,o,o,o,o,M,M,M],
> [o,o,o,M,o,o,o,o,o,M,o],
> [o,o,o,M,o,M,M,o,o,o,o],
> [o,o,o,o,M,M,M,M,o,o,o],
> [o,o,o,M,M,M,M,M,M,M,o],
> [o,o,o,M,M,o,M,M,M,o,o],
> [o,o,o,o,o,o,M,M,o,o,o],
> [M,M,o,o,o,M,o,o,o,o,o],
> [o,o,o,o,o,o,o,o,o,o,o]]
>
> def continent_size world, x, y
> if x > 10 && y > 10
> size = 0
> else
> if world[x][y] != ' land '
> return 0
> end
> end
> # Either it ' s water or we already
> # counted it, but either way, we don ' t
> # want to count it now.
>
>
> # So first we count this tile...
> size = 1
> world[x][y] = ' counted land '
> # ...then we count all of the
> # neighboring eight tiles (and,
> # of course, their neighbors by
> # way of the recursion).
> size = size + continent_size(world, x-1, y-1)
> size = size + continent_size(world, x , y-1)
> size = size + continent_size(world, x+1, y-1)
> size = size + continent_size(world, x-1, y )
> size = size + continent_size(world, x+1, y )
> size = size + continent_size(world, x-1, y+1)
> size = size + continent_size(world, x , y+1)
> size = size + continent_size(world, x+1, y+1)
> size
> end
>
> puts continent_size(world, 5, 5)
--
Posted via http://www.ruby-forum.com/.
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups "Ruby
on Rails: Talk" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en
-~----------~----~----~----~------~----~------~--~---
