A two-dimensional array can be thought of as a series of one-dimensional arrays stacked on top of each other. It has rows and columns. To declare a two-dimensional array, use int[][] and specify the number of rows and columns by initializing it with new int[rows][columns]. A two-dimensional array can be iterated through using nested for loops, with the outer loop iterating through rows and the inner loop iterating through columns.

1. Two-Dimensional
Arrays
Chapter 11

2. 11
What is a two-dimensional array?
A two-dimensional
array has “rows”
and “columns,”
and can be thought
of as a series of
one-dimensional
arrays stacked on
top of one another.

3. 11
Declare a two-dimensional array:
int[][] anArray = new int[5][5];
Declaring a Two-Dimensional Array

4. 11
Iterating a Two-Dimensional Array
Use a nested for loop:
Outer loop iterates the row
Inner loop iterates the column.
for ( int i=0; i<5; i++ )
{
for ( int j=0; j<5; j++ )
{
anArray[i][j] = i+j;
}
}

5. 11
Multidimensional Arrays
Arrays can have more than two
dimensions.
Multidimensional arrays are not
commonly used as they quickly become
difficult to manage.
Declare multidimensional array:
int[][][] anArray = new
int[5][5][5];

6. 11
Implementing Cellular Automata
One generation
per row
One-dimensional
array holds on/off
status of each cell
in each generation

7. 11
The Game of Life
Using two-dimensional arrays:
Entire board is
one generation.
Two-dimensional
array holds state of
each cell of the game
board organized in
rows and columns.