//  File:  ArrayDemo.java

//  Creates an int array of exactly "size" elements, where size is a
//  random int between 25 and 50, inclusive.  Fills the array with 
//  random ints between 10 and 99, inclusive, and prints it.  Then sorts
//  the array and prints it again.
//
//  Shows a class with an array instance variable, declaring an array
//  object variable and creating an array object, traversing an array
//  using a "for" statement, the "length" instance variable, and using
//  random ints.
//
//  Note: To get a random int between two positive ints, a and b, inclusive,
//  using a Random object, r, use:  r.nextInt(b - a + 1) + a
import java.util.Random;

class BogusList
{
    // instance variable - an int array object variable
    private int[] list;

    public BogusList(int size)  // constructor
    {
        System.out.println("Creating an array object with " + size + 
                           " elements...\n");
        list = new int[size];
    }

    public void fill() 	// fill array w/ random ints
    {
        Random r = new Random();
        System.out.println("Filling array with " + list.length + 
                           " random ints between 10 and 99, inclusive...\n");
        for (int i = 0; i < list.length; i++)
        {
            list[i] = r.nextInt(90) + 10;
        }
    }

    public void sort()	// ascending selection sort
    {
        // for each element, i, from 0 to next-to-last...
        for (int i = 0; i < list.length - 1; i++)
        {
            // ...find smallest value in elements i+1 through last...
            int minPos = i;
            for (int j = i + 1; j < list.length; j++)
            {
                if (list[j] < list[minPos])
                {
                    minPos = j;
                }
            }
            // ...and swap it with element i
            int temp = list[i];
            list[i] = list[minPos];
            list[minPos] = temp;
        }
    }

    public void print()     // print array 10 elements per line 
    {
        for (int i = 0; i < list.length; i++)
        {
            System.out.print(list[i] + "   ");
            if ((i + 1) % 10 == 0)
            {
                System.out.println();
            }
        }
        System.out.println();
    }
}

public class ArrayDemo
{

    public static void main(String args[])
    {
        // create random number generator object, called r...
        Random r = new Random();

        // get random number between 25 and 50, inclusive, for size of array
        int listSize = r.nextInt(26) + 25;

        // pass array size to BogusList constructor...
        BogusList numbers = new BogusList(listSize);

        // fill the array...
        numbers.fill();

        // print it...
        System.out.println("The original list:\n");
        numbers.print();

        // sort it...
        numbers.sort();

        // print sorted array...
        System.out.println("\nThe sorted list:\n");
        numbers.print();

        System.out.println();
    }
}
                 
/*  Sample output:

Creating an array object with 37 elements...

Filling array with 37 random ints between 10 and 99, inclusive...

The original list:

95   87   84   28   50   40   93   86   67   32
33   67   96   94   89   66   44   62   28   92
33   70   43   76   68   53   44   74   23   29
49   70   36   46   77   46   79

The sorted list:

23   28   28   29   32   33   33   36   40   43
44   44   46   46   49   50   53   62   66   67
67   68   70   70   74   76   77   79   84   86
87   89   92   93   94   95   96

*/