• Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Liutauras Vilda
  • Bear Bibeault
  • Jeanne Boyarsky
  • Tim Cooke
Sheriffs:
  • Knute Snortum
  • Junilu Lacar
  • Devaka Cooray
Saloon Keepers:
  • Ganesh Patekar
  • Tim Moores
  • Carey Brown
  • Stephan van Hulst
  • salvin francis
Bartenders:
  • Ron McLeod
  • Frits Walraven
  • Pete Letkeman

Multidimensional Arrays  RSS feed

 
Ranch Hand
Posts: 45
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

[ans]
Hello Everyone
Can Anyone explain me what is the answer of the above program
and why ?
[/ans]
 
Ranch Hand
Posts: 7729
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Please mention the source of any mock exam question that you post.
 
Ranch Hand
Posts: 52
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
The only one I know that would work is "B" but I don't know the others.

Could someone give an idea of how to draw/map this out on paper so we could figure it out for ourselves?

Thanks
 
Ranch Hand
Posts: 78
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
The answer is A, B, E and F (correct me if you disagree!)

A: b2[0][1] refers to a 2d array, which b is.
B: b[0][0] refers to a byte value, which b3 is.
E: b2[0][1][0][0] refers to a single byte value, as does b[0][0]
F: b2[0][1] refers to a 2d array, which 'big' is.

C: b2[1][1][0] refers to a 1d array, whereas b[0][0] refers to a single byte
D: b2[1][2][0] refers to a 1d array, whereas b is a 2d array

If you can't just see the number of dimensions when looking at the code you could look at an array like this:

byte b2 [][][][] = new byte [2][3][1][2]; //a 4d array

If you put:
b2[0][1][0][0] you're referring to a single value
b2[0][1][0] you're referring to a 1d array
b2[0][1] you're referring to a 2d array
b2[0] you're referring to a 3d array
b2 you're referring to a 4d array

Notice the pattern - so you could apply this to other arrays:

e.g
byte [][] b = new byte [2][1]; //a 2d array

b[0][0] single value
b[0] 1d array
b 2d array

There might be easier ways of working this out but I think once you're familiar with working with arrays (through practise) it's like doing timestables and the answer is obvious.
[ November 27, 2006: Message edited by: Andy Morris ]
 
Greg L Tonn
Ranch Hand
Posts: 52
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Andy,

So it doesn't matter what the size of the array is only the demensions?
 
Andy Morris
Ranch Hand
Posts: 78
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
For compilation only the dimensions matter.
For runtime the size does matter (you'll get ArrayIndexOutOfBoundsExceptions if you reference an index that is not valid).
 
Ranch Hand
Posts: 60
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Thanks Andy for your inputs.It really helped.

Regards

Nikhil
 
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime.
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!