2d array java initialize code example

Example 1: 2d array java

//Length
int[][]arr= new int [filas][columnas];
arr.length=filas;

        int[][] a = {
            {1, 2, 3}, 
            {4, 5, 6, 9}, 
            {7}, 
        };
      
        // calculate the length of each row
        System.out.println("Length of row 1: " + a[0].length);
        System.out.println("Length of row 2: " + a[1].length);
        System.out.println("Length of row 3: " + a[2].length);
    }

Example 2: Java 2d array initialization

class TwoDimensionalArray {

    public static void main(String[] args) {
        String[][] salutation = {
            {"Mr. ", "Mrs. ", "Ms. "},
            {"Kumar"}
        };

        // Mr. Kumar
        System.out.println(salutation[0][0] + salutation[1][0]);

        // Mrs. Kumar
        System.out.println(salutation[0][1] + salutation[1][0]);
    }
}

The output from this program is:

Mr. Kumar
Mrs. Kumar

Example 3: how to initialize one dimensional array in java

int[] a; // valid declaration
int b[]; // valid declaration 
int[] c; // valid declaration