public static void main(String[] args) {

Scanner in = new Scanner(System.in);

/* look like matrices.

// the no. of rows are mandatory but no. of columns are optional.

int[][] arr2D = {

{1, 2, 3},

{4, 5, 6},

{7, 8, 9}

}; //can be written directly like this

// size of the individual rows can be different.

// internal working:

// int[][] arr = new int[3][];

// int[][] arr2D = {

// {1, 2, 3}, // 0th index

// {4, 5}, // 1st index

// {6, 7, 8, 9} // 2nd index -> for eg: arr2D[2] = {6, 7 8, 9}

// };

// input

// input for all arrays inside of bigger array

// this will print every data in an array and loop will terminate after completing its size (or length)

// arr.length = gives no. of rows

// take input for each column in every row.

//Input for row:

int[][] arr = new int[3][3];

//System.out.println(arr.length); // print no. of rows

// taking input:

for (int row = 0; row < arr.length; row++) {

// for each column in every row

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

arr[row][col] = in.nextInt();

}

}

//output:

// for (int row = 0; row < arr.length; row++) {

// // for each column in every row

// for (int col = 0; col < arr[row].length; col ++) {

// System.out.print(arr[row][col]+ " ");

// }

// System.out.println();

// }

//output

// for (int row = 0; row < arr.length; row++) {

// System.out.println(Arrays.toString(arr[row]));

// }

// enhanced for loop for array

for (int[] a : arr) {

System.out.println(Arrays.toString(a));

}

// to print string with enhanced for loop.

// for (String element : arr) {

// System.out.println(element);

// }

}