Problema libro de Robert Lafore

Problema #6 - pág. 76
Data Structures and Algorithms in Java (2nd Edition)
by Robert Lafore

HighArrayApp.java
===========================
/*
* Created on 06/20/2005
*
* Problema #6 - pág. 76
* Data Structures and Algorithms in Java (2nd Edition)
* by Robert Lafore
*
* Descripcion:
* 2.6 write a noDups() method for the HighArray class
* of the highArray.java program (Listing 2.3). This method should
* remove all duplicates from the array. That is, if three items
* with the key 17 appear in the array, noDups() should remove two of them.
* Don't worry about maintaining the order of the items. One approach
* is to first compare every item with all the other items and overwrite
* any duplicates with a null (or a distinctive value that ins't used for
* real keys). Then remove all the nulls. Of course, the array size
* will be reduced.
*/
package estructura;

/**
* @author vns
*
*/

//highArray.java
//demonstrates array class with high-level interface
//to run this program: C>java HighArrayApp

////////////////////////////////////////////////////////////////
class HighArray
{
private double[] a; // ref to array a
private int nElems; // number of data items
//----------------------------------------------------------

public HighArray(int max) // constructor
{
a = new double[max]; // create the array
nElems = 0; // no items yet
}
//----------------------------------------------------------

public boolean find(double searchKey)
{ // find specified value
int j;
for(j=0; j < nElems; j++) // for each element,
if(a[j] == searchKey) // found item?
break; // exit loop before end
if(j == nElems) // gone to end?
return false; // yes, can't find it
else
return true; // no, found it
} // end find()
//----------------------------------------------------------

public void insert(double value) // put element into array
{
a[nElems] = value; // insert it
nElems++; // increment size
}
//----------------------------------------------------------

public boolean delete(double value)
{
int j;
for(j=0; j < nElems; j++) // look for it
if( value == a[j] )
break;
if(j==nElems) // can't find it
return false;
else // found it
{
for(int k=j; k < nElems; k++) // move higher ones down
a[k] = a[k+1];
nElems--; // decrement size
return true;
}
} // end delete()
//----------------------------------------------------------

public void display() // displays array contents
{
for(int j=0; j < nElems; j++) // for each element,
System.out.print(a[j] + " "); // display it
System.out.println("");
}
//----------------------------------------------------------

public void noDups()
{
int j;
for(j=0; j < nElems; j++) // look for it
for (int i = j; i < nElems; i++)
if( (a[j] == a[i]) && (i != j) && (a[j] != -1) && (a[i] != -1) )
a[i] = -1;

if (j == nElems) // can't find it
return;

for(int k=0; k < nElems; k++){
if ( a[k] == -1 )
delete(a[k]); // delete all -1 value
}
} // end noDups()
//----------------------------------------------------------

} // end class HighArray
////////////////////////////////////////////////////////////////
class HighArrayApp
{
public static void main(String[] args)
{
int maxSize = 100; // array size
HighArray arr; // reference to array
arr = new HighArray(maxSize); // create the array
arr.insert(77); // insert 10 items
arr.insert(99);
arr.insert(44);
arr.insert(55);
arr.insert(22);
arr.insert(88);
arr.insert(11);
arr.insert(00);
arr.insert(66);
arr.insert(33);
arr.display(); // display items
int searchKey = 35; // search for item
if( arr.find(searchKey) )
System.out.println("Found " + searchKey);
else
System.out.println("Can't find " + searchKey);
arr.delete(00); // delete 3 items
arr.delete(55);
arr.delete(99);
arr.display(); // display items again
} // end main()
} // end class HighArrayApp