Thread: 2d Array

42 0 33 67 145 41 23 7 8 255
234 0 0 157 0 0 0 0 1 5
167 0 143 0 0 0 8 1 7 255
178 2 41 0 0 0 255 1 6 6
189 3 1 0 0 0 0 0 5 8
0 0 0 93 78 1 0 157 63 143
53 0 0 0 0 2 255 4 0 165
156 0 0 0 5 2 143 0 0 0
69 0 0 0 74 63 35 0 0 0
73 34 3 0 0 0 234 0 0 0


You need to create a class, named MicroArray, which contains the following methods

- Print out the input 2D-array as an image on the console screen.
• Replace 0 by “ ” {space}.
• Replace values between 1 and 99 by “.” {one dot}.
• Replace values between 100 and 199 by “..” {two dots}.
• Replace values between 200 and 254 by “…” {three dots}.
• Replace 255’s by “x”.
- Remember to check if the dimensions of input array are valid numbers.
- Make use of method printf properly to print out the image nicely.

Need help getting this started kind of confused on 2 dimensional arrays?

Well, once you have a basic understanding of 2d arrays, the rest of the program is just a bunch of if/else if statements and nested for loops.

As for a starting point, I'd recommend finding a good tutorial over 2d arrays to give you a basic understanding of them. I really can't think of any off the top of my head, but a quick Google search may bring you to several which can help.

Basically, you just need to know that a 2d array is just a regular array with multiple rows. To create one, you just add another [] such as:

int[][] anArray = new int[[I]number of rows here[/I]][[I]number of columns here[/I]]

As far as putting values inside the array, there are a couple ways you can do that. You can use a nested for loop, for example if you wanted all values to be 0:

for (int row = 0; row < anArray.length; row ++)
       for (int col = 0; col < anArray[row].length; col++)
              anArray[row][col] = 0;

Or if you know the exact values and where they belong, which seems like you do in this case, you can do something like this:

int[][] anArray = {{1, 2, 3},
                          {4, 5, 6},
                          {7, 8, 9}}

I hope this helps you get started!