问题
I am preparing for OCAJP exam, I got a problem with the multi-dimensional arrays in java. After go through a video tutorial on YouTube, I think I got an idea about how it works. It says the following statement creates two double dimensional arrays and one array to hold both arrays. Hence it is a three dimensional array.
int arr[][][] = new int[2][4][3];
So I want to get confirmed, that if I want a five dimensional array, this statement would do it.
int arr[][][] = new int[4][4][3];
回答1:
Try to visualise it geometrically.
A 1-dimensional array is just a list:
new int[2]A 2-dimensional array is a rectangular grid (or a list of lists):
new int[2][3]A 3-dimensional array is a cuboid (or a list of rectangles, or a list of lists of lists):
new int[2][3][4]
After this it gets harder, but :
a 4D array is a list of cuboids (a list of lists of lists of lists)
new int[2][3][4][5]a 5D array is a grid of cuboids (a list of lists of lists of lists of lists):
new int[2][3][4][5][6]
回答2:
int arr[][][] = new int[4][4][3];
Is still a 3 dimensional array.
A 5 dimensional array looks like
int arr[][][][][] = new int[4][4][3][4][3];
回答3:
int arr[][][][][] = new int[4][4][3][X][X];
x can be any number. this is a 5 dimentional array.
回答4:
Imagine a cube.
int arr[][][] = new int[2][4][3];
Here you have 2 slices of an array of 4x3.
int arr[][][] = new int[4][4][3];
With this, you have 4 slices of an array of 4x3.
So, it stills a three dimensional array. However, you can save 4 different two dimensional arrays there.
回答5:
every time you add a new dimension the number of elements grow exponentially. int[4][4][3] means a 3-dimensions array with 4*4*3=48 elements. to create a 5-dimension array add 2 more square-brackets int[2][2][2][2][2] which is an array with 2^5 elements(2*2*2*2*2)
来源：https://stackoverflow.com/questions/24597504/multi-dimensional-arrays-in-java