Multidimensional Arrays lengths in Java

Question

How to find the lengths of a multidimensional array with non equal indices?

For example, I have int[][] pathList = new int[6][4]

Without actuall

Answer 1

In Java we can't use Length field like we used to one-dimensional arrays. So simply writing a few lines of code solves this problem. First, you need to know that the output of the Length field in multidimensional arrays is the number of rows.I mean when you have below array

int[][] numbers = {{1,2,3,4,2,6},{4,5,6,7}};

the result of System.out.println(numbers.length); is 2, because you have 2 rows. So, you should use this to solve this problem. Example:

public class Main {

public static void main(String[] args) {

    //Array definition
    int[][] numbers = {{1,2,3,4,2,6},{4,5,6,7}};

    //Number of array's elements
    int result = 0;

    //calculate via loop
    for(int i=0; i< numbers.length; i++){
        result +=  numbers[i].length;
    }

    //output
    System.out.println(result);
}

}

Answer 2

3-D array length

int[][][] a = new int[2][3][7];
int length=0;
for(int[][] i:a){
    for(int j[]:i){
        length+=j.length;
    }   
}           
System.out.println(length);