Thursday, October 28, 2010
MIDTERM - InsertionSortTest
/*
Insertion Sort Midterm
*/
import java.util.Random;
public class InsertionSort
{
private int[] data; //array of values
private static Random generator = new Random();
//create array of given size to fill
public InsertionSort( int size )
{
data = new int[size]; //create space for arrays
//fill arrays with random numbers 10-99
for( int i = 0; i < size; i++ )
data[i] = 10 + generator.nextInt(90);
}
//sort array using insertion sort
public void sort()
{
int insert; //temp; variable to hold element to insert
//loop over data.length - elements
for( int next = 1; next < data.length; next++ )
{
//sort value in current element
insert = data[next];
//initialize location to place element
int moveItem = next;
//search for place to put current element
while( moveItem > 0 && data[moveItem - 1] > insert )
{
//shift element right one slot
data[moveItem] = data[moveItem - 1];
moveItem--;
}
data[moveItem] = insert; //place inserted element
printPass( next, moveItem ); //output pass of algorithm
}
}
//print a pass of the algorithm
public void printPass( int pass, int index )
{
System.out.print( String.format( "after pass %2d: ", pass ) );
//output elements till swapped item
for( int i = index + 1; i < data.length; i++ )
System.out.print( data[i] + " ");
System.out.print( "\n " ); //for allignment
//indicate amount of array that is sorted
for( int i = 0; i <= pass; i++ )
System.out.print( "-- " );
System.out.println( "\n" ); //add endline
}
//method to output values in array
public String toString()
{
StringBuilder temporary = new StringBuilder();
//iterate through array
for ( int element : data )
temporary.append( element + " " );
temporary.append( "\n" ); //add endline character
return temporary.toString();
}
}
---------------------------------------------------------------------------------
/*
main function MIDTERM
*/
public class InsertionSortTest
{
public static void main( String[] args )
{
//create object to perform insertion sort
InsertionSort sortArray = new InsertionSort( 10 );
System.out.println( "Unsorted array: " );
System.out.println( sortArray ); //print unsorted array
sortArray.sort();
System.out.println( "Sorted array: " );
System.out.println( sortArray ); //print sorted array
}
}
Wednesday, October 27, 2010
Assignment 14 - Merge Sort Test
/*
Merge Sort
*/
import java.util.Random;
public class MergeSort
{
private int[] data; //array of values
private static Random generator = new Random();
//create array of given size and fill with random integers
public MergeSort( int size )
{
data = new int[size]; //create space for array
//fill array with random ints range 10-99
for( int i = 0; i < size; i++ )
data[i] = 10 + generator.nextInt( 90 );
}
//calls recursive split method to begin merge sorting
public void sort()
{
sortArray( 0, data.length - 1); //split entire array
}
//splits array, sort subarrays and merges subarrays into sorted array
private void sortArray( int low, int high )
{
//test case: size of array equals 1
if( ( high - low ) >= 1 ) //if not base case
{
int middle1 = (low + high )/2; //calculate middle of array
int middle2 = middle1 + 1; //calculate next element over
//output split step
System.out.println( "split: " + subarray( low, high ) );
System.out.println( " " + subarray( low, middle1 ) );
System.out.println( " " + subarray( middle2, high ) );
//split array in half; sort each half of array
sortArray( low, middle1 ); //first half of array
sortArray( middle2, high ); //second half of array
//merge 2 sorted arrays after split calls return
merge( low, middle1, middle2, high );
}
}
//merge 2 sorted subarrays into one sorted sub array
private void merge( int left, int middle1, int middle2, int right )
{
int leftIndex = left; //index into left subarray
int rightIndex = middle2; //index into right subarray
int combinedIndex = left; //index into temp. work array
int[] combined = new int[data.length]; //working array
//output 2 subarrays before merging
System.out.println( "merge: " + subarray( left, middle1 ) );
System.out.println( " " + subarray( middle2, right ) );
//merge arrays until reaching end of either
while( leftIndex <= middle1 && rightIndex <= right )
{
//place smaller of 2 current elements into result
//and move to next space in arrays
if( data[leftIndex] <= data[rightIndex] )
combined[combinedIndex++] = data[leftIndex++];
else
combined[combinedIndex++] = data[rightIndex++];
}
//if array is empty
if( leftIndex == middle2 )
//copy in rest of right array
while( rightIndex <= right )
combined[combinedIndex++] = data[rightIndex++];
else
//copy in rest of left array
while( leftIndex <= middle1 )
combined[combinedIndex++] = data[leftIndex++];
//copy values back into original array
for( int i = left; i <= right; i++ )
data[i] = combined[i];
//output merged array
System.out.println(" " + subarray( left, right ) );
System.out.println();
}
//method to output certain values in array
public String subarray( int low, int high )
{
StringBuilder temporary = new StringBuilder();
//output spaces for alignment
for( int i = 0; i < low; i++ )
temporary.append( "" );
//output elements left in array
for( int i = low; i <= high; i++ )
temporary.append( "" + data[i] );
return temporary.toString();
}
//method to output values in array
public String toString()
{
return subarray( 0, data.length - 1 );
}
}
--------------------------------------------------------------------------
/*
main function
*/
public class MergeSortTest
{
public static void main( String[] args )
{
//create object to perform merge sort
MergeSort sortArray = new MergeSort(10);
//print unsorted array
System.out.println( "Unsorted: " + sortArray + "\n" );
sortArray.sort(); //sort array
//print sorted array
System.out.println( "Sorted: " + sortArray );
}
}
Thursday, October 21, 2010
Assignment 13 - Insertion Sort Test
/*
Assignment 13
Insertion Sort
*/
import java.util.Random;
public class InsertionSort
{
private int[] data; //array of values
private static Random generator = new Random();
//create array of given size to fill
public InsertionSort( int size )
{
data = new int[size]; //create space for arrays
//fill arrays with random numbers 10-99
for( int i = 0; i < size; i++ )
data[i] = 10 + generator.nextInt(90);
}
//sort array using insertion sort
public void sort()
{
int insert; //temp; variable to hold element to insert
//loop over data.length - elements
for( int next = 1; next < data.length; next++ )
{
//sort value in current element
insert = data[next];
//initialize location to palce element
int moveItem = next;
//search for place to put current element
while( moveItem > 0 && data[moveItem - 1] > insert )
{
//shift element right one slot
data[moveItem] = data[moveItem - 1];
moveItem--;
}
data[moveItem] = insert; //place inserted element
printPass( next, moveItem ); //output pass of algorithm
}
}
//print a pass of the algorithm
public void printPass( int pass, int index )
{
System.out.print( String.format( "after pass %2d: ", pass ) );
//output elements till swapped item
for( int i = index + 1; i < data.length; i++ )
System.out.print( data[i] + " ");
System.out.print( "\n " ); //for allignment
//indicate amount of array that is sorted
for( int i = 0; i <= pass; i++ )
System.out.print( "-- " );
System.out.println( "\n" ); //add endline
}
//method to output values in array
public String toString()
{
StringBuilder temporary = new StringBuilder();
//iterate through array
for ( int element : data )
temporary.append( element + " " );
temporary.append( "\n" ); //add endline character
return temporary.toString();
}
}
---------------------------------------------------------------------------------
/*
Assignment 13
main function
*/
public class InsertionSortTest
{
public static void main( String[] args )
{
//create object to preform insertion sort
InsertionSort sortArray = new InsertionSort( 10 );
System.out.println( "Unsorted array: " );
System.out.println( sortArray ); //print unsorted array
sortArray.sort();
System.out.println( "Sorted array: " );
System.out.println( sortArray ); //print sorted array
}
}
Monday, October 18, 2010
Assignment 12 - Selection Sort Test
/*
Selection Sort Algorithm
*/
import java.util.Random;
public class SelectionSort
{
private int[] data; //array of value
private static Random generator = new Random();
//create array if given size and fill w/ random int
public SelectionSort( int size )
{
data = new int[size]; //create space for array
//fill array with random int 10-99
for(int i = 0; i < size; i++ )
data[i] = 10 + generator.nextInt( 90 );
}
//sort array using slection sort
public void sort()
{
int smallest; //index of smallest element
//loop over data length -1
for(int i = 0; i < data.length - 1; i++)
{
smallest = i; //first index of remaining array
//loops to find index of smallest element
for( int index = i + 1; index < data.length; index++)
if(data[index] < data[smallest])
smallest = index;
swap( i, smallest); //swap smallest elements into position
printPass( i + 1, smallest );
}
}
//helper method to swap values in two elements
public void swap( int first, int second )
{
int temporary = data[first]; // store first in temporary
data[first] = data[second]; // replace first with second
data[second] = temporary; // put temporary in second
}
//print a pass of algorigthm
public void printPass( int pass, int index )
{
System.out.print( String.format( "after pass %2d; ", pass) );
//output elements till selectem item
for (int i = 0; i < index; i++)
System.out.print( data[i] + "");
System.out.print( "\n "); //for alignment
//indicate amount of array that is sorted
for( int j = 0; j < pass; j++ )
System.out.println("\n"); //add endline
}
//method to output balues in array
public String toString()
{
StringBuilder temporary = new StringBuilder();
//iterate through array
for( int element : data)
temporary.append( element + " " );
temporary.append("\n");
return temporary.toString();
}
}
-------------------------------------------------------------------
/*
main function
*/
public class SelectionSortTest
{
public static void main( String[] args )
{
//create object to perform selection sort
SelectionSort sortArray = new SelectionSort(10);
System.out.println( "Unsorted array:" );
System.out.println( sortArray ); //print unsorted array
sortArray.sort(); //sort array
System.out.println( "Sorted Array:" );
System.out.println( sortArray ); //print sorted array
}
}
Thursday, October 7, 2010
Towers of Hanoi
/* Towers of Hanoi */
public class TowersOfHanoi
{
private int numDisks; //number of disks to move
public TowersOfHanoi( int disks )
{
numDisks = disks;
}
//recursively more disks between towers
public void solveTowers(int disks, int sourcePeg, int destinationPeg, int tempPeg)
{
//base case -- only one disk to move
if( disks == 1)
{
System.out.printf("\n%d --> %d",sourcePeg, destinationPeg);
return;
}
//recursion step -- move (disk -1) disk from sourcePeg
//to tempPEg using destinationPeg
solveTowers(disks-1,sourcePeg,tempPeg,destinationPeg);
//move last disk from sourcePeg to destinationPeg
System.out.printf("\n%d --> %d", sourcePeg, destinationPeg);
//move (disk-1) disk from tempPeg to destinationPeg
solveTowers( disks - 1, tempPeg, destinationPeg, sourcePeg);
}
}
--------------------------------------------------------------------
/* Main function to be run */
public class TowersOfHanoiTest
{
public static void main( String args[])
{
int startPeg = 1; // value 1 used to indicate startPeg in output
int endPeg = 3; // value 3 usedto indicate endPeg in output
int tempPeg = 2; // value 2 used to indicate tempPeg output
int totalDisks = 3; // number of disks
TowersOfHanoi towersOfHanoi = new TowersOfHanoi(totalDisks);
//initial nonrecursive call: move all disks
towersOfHanoi.solveTowers(totalDisks, startPeg, endPeg, tempPeg);
}
}
Binary Search Test
/*
Assignment #
*/
import java.util.Random;
import java.util.Arrays;
public class BinaryArray
{
private int[] data; //array of any value
private static Random generator = new Random();
//create array of any size and fill with random int
public BinaryArray( int size )
{
data = new int[ size ]; //create space for array
//fill array with int 10-99
for(int i=0; i
data[ i ] = 10 + generator.nextInt( 90 );
Arrays.sort( data );
}
//preform binary search in data
public int binarySearch( int searchElement )
{
int low = 0; //low end of search area
int high = data.length - 1; //high end of search area
int middle = (low + high + 1)/2; //middle element
int location = -1; //retunr value; -1 if not found
do //loop to search element
{
//print remaining elements of array
System.out.print( remainingElements( low, high ) );
//output spaces for alignment
for(int i=0; i
System.out.print( " " );
System.out.println( " * " ); //indicate current middle
//if the element is found at the middle
if(searchElement == data[ middle ])
location = middle; //location is the current middle
//middle element is too high
else if(searchElement
high = middle - 1; //eliminate the higher half
else //middle element too low
low = middle + 1; //eliminate the lower half
middle = (low + high + 1)/2; //recalculate the middle
}
while( (low <= high) && (location == -1) );
return location; //return location of search key
}
//method to output certain values in array
public String remainingElements( int low, int high )
{
StringBuilder temporary = new StringBuilder();
//output spaces for alignment
for(int i=0; i
temporary.append(" ");
//output elements left in array
for(int i=low; i<=high; i++)
temporary.append( data[ i ] + " " );
temporary.append( "\n" );
return temporary.toString();
}
//method to output values in array
public String toString()
{
return remainingElements( 0, data.length - 1);
}
}
-------------------------------------------------------------------
import java.util.Scanner;
public class BinarySearchTest
{
public static void main( String args[] )
{
// create Scanner object to input data
Scanner input = new Scanner( System.in );
int searchInt; //search key
int position; //location of search key in array
//create array and output it
BinaryArray searchArray = new BinaryArray( 15 );
System.out.println( searchArray );
//get input from user
System.out.print( "Please enter an integer value (-1 to quit): ");
searchInt = input.nextInt(); //read an int from user
System.out.println();
//repeadtedly ubput an integer; -1 terminates the program
while(searchInt != -1)
{
//use binary search to try to find integer
position = searchArray.binarySearch( searchInt );
//return value of -1 indicates indicates integer was not found
if(position == -1)
System.out.println( "The integer " + searchInt + " was not found.\n" );
else
System.out.println( "The integer " + searchInt + " was found in position "
+ position + ".\n" );
//get input from user
System.out.print( "Please enter an integer value (-1 to quit): " );
searchInt = input.nextInt(); //read an int from user
System.out.println();
}
}
}
Subscribe to:
Posts (Atom)