Create an Evaluator class that will evaluate the sorting algorithms. Create 1 me
ID: 3816847 • Letter: C
Question
Create an Evaluator class that will evaluate the sorting algorithms. Create 1 method for each of the sorting algorithms below. Each method must accept 1 int[]as a parameter.
Selection sort
Insertion sort
Merge sort
Implement the code for each of the sort methods above by referring to Figures 19.6
// Fig. 19.6: SelectionSortTest.java
// Sorting an array with selection sort.
import java.security.SecureRandom;
import java.util.Arrays;
public class SelectionSortTest
{
// sort array using selection sort
public static void selectionSort(int[] data)
{
// loop over data.length - 1 elements
for (int i = 0; i < data.length - 1; i++)
{
int smallest = i; // first index of remaining array
// loop to find index of smallest element
for (int index = i + 1; index < data.length; index++)
if (data[index] < data[smallest])
smallest = index;
swap(data, i, smallest); // swap smallest element into position
printPass(data, i + 1, smallest); // output pass of algorithm
}
} // end method selectionSort
// helper method to swap values in two elements
private static void swap(int[] data, 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 the algorithm
private static void printPass(int[] data, int pass, int index)
{
System.out.printf("after pass %2d: ", pass);
// output elements till selected item
for (int i = 0; i < index; i++)
System.out.printf("%d ", data[i]);
System.out.printf("%d* ", data[index]); // indicate swap
// finish outputting array
for (int i = index + 1; i < data.length; i++)
System.out.printf("%d ", data[i]);
System.out.printf("%n "); // for alignment
// indicate amount of array that’s sorted
for (int j = 0; j < pass; j++)
System.out.print("-- ");
System.out.println();
}
public static void main(String[] args)
{
SecureRandom generator = new SecureRandom();
int[] data = new int[10]; // create array
for (int i = 0; i < data.length; i++) // populate array
data[i] = 10 + generator.nextInt(90);
System.out.printf("Unsorted array:%n%s%n%n",
Arrays.toString(data)); // display array
selectionSort(data); // sort array
System.out.printf("Sorted array:%n%s%n%n",
Arrays.toString(data)); // display array
}
} // end class SelectionSortTest
2. Exclude any portions of the textbook code that print anything to the output window. The goal here is to evaluate the efficiency of the sort algorithms, not how quickly they can print things to the console.
3. Add 3 further methods to the Evaluator class that perform the following tasks:
Returns an array with 100,000 int values in sequential order, starting with 1 and ending with 100,000.
Returns an array with 100,000 random int values.
Returns an array with 100,000 int values in descending sequential order, starting with 100,000 and ending with 1.
4. Take a screenshot of your output table Following the screenshot discuss if your observed values are consistent with the Big O notation
Explanation / Answer
//As you have already given selection sort code i have made the changes to the same.
//below is the program with 10000 random numbers generated and the slection sort with descending order.
import java.security.SecureRandom;
import java.util.Arrays;
class SelectionSortTest
{
// sort array using selection sort
public static void selectionSort(int[] data)
{
// loop over data.length - 1 elements
for (int i = 0; i < data.length - 1; i++)
{
int smallest = i; // first index of remaining array
// loop to find index of smallest element
for (int index = i + 1; index < data.length; index++)
if (data[index] < data[smallest])
smallest = index;
swap(data, i, smallest); // swap smallest element into position
printPass(data, i + 1, smallest); // output pass of algorithm
}
} // end method selectionSort
public static void descending(int[] data)
{
int temp,i;
int j;
for ( i = 0; i < data.length; i++)
{
for ( j = i + 1; j < data.length; j++)
{
if (data[i] < data[j])
{
temp = data[i];
data[i] = data[j];
data[j] = temp;
}
}
}// swap smallest element into position
System.out.print("Descending Order:");
for ( i = 0; i < data.length; i++)
System.out.printf("%d ", data[i]);
}
// helper method to swap values in two elements
private static void swap(int[] data, 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 the algorithm
private static void printPass(int[] data, int pass, int index)
{
System.out.printf("after pass %2d: ", pass);
// output elements till selected item
for (int i = 0; i < index; i++)
System.out.printf("%d ", data[i]);
System.out.printf("%d* ", data[index]); // indicate swap
// finish outputting array
for (int i = index + 1; i < data.length; i++)
System.out.printf("%d ", data[i]);
System.out.printf("%n "); // for alignment
// indicate amount of array that sorted
for (int j = 0; j < pass; j++)
System.out.print("-- ");
System.out.println();
}
public static void main(String[] args)
{
SecureRandom generator = new SecureRandom();
int[] data = new int[10000]; // create array
for (int i = 0; i < data.length; i++) // populate array
data[i] = 10 + generator.nextInt(99990);
System.out.printf("Unsorted array:%n%s%n%n",
Arrays.toString(data)); // display array
selectionSort(data); // sort array
System.out.printf("Sorted array in ascending:%n%s%n%n",
Arrays.toString(data)); // display array
descending(data);
//System.out.printf("Sorted array in descending:%n%s%n%n",
// Arrays.toString(data));
}
}
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