// create array using 1D arrays

public class aoa0  {
    public static void main(String args[]) {

        // Create ragged array with default values:

	   final int ROWS = 2;
	   int[][] a = new int[ROWS][];

        // Create array $r0$ to store values 1 and 2:

	   int[] r0 = new int[2];
	   r0[0] = 1; r0[1] = 2;
	   // also, int[] r0 = {1,2};
        
        // Create array $r1$ to store values 3, 4, 5:

	   int[] r1 = new int[3];
	   r1[0] = 3; r1[1] = 4; r1[2] = 5;
        
        // Store refs to arrays $r0$ and $r1$ in
        // 1st and 2nd elements of array $a$:

           a[0] = r0;
           a[1] = r1;

        // Use $a[i][j]$ to access elements:

           for ( int i=0 ; i < a.length ; i++) {        // "rows"
	       for ( int j = 0 ; j < a[i].length ; j++) // "cols"
		   System.out.print(a[i][j] +" ") ;     // element
	       System.out.println();                    // skip lines between rows
           }

    } // method main

} // class aoa0

/* output:
1 2 
3 4 5
*/