Question

PLEASE ANSWER #5AND #6, THE ANSWER FOR #3 AND #4 ARE ALREADY PROVIDED!!! 3

.Using Java, Write a computer program that prompts the user for one number, n for the number of items in the array to sort, and create and sort 1000 arrays of this size timing the run to get an average time to sort an array of this size. Then do the following: Initiate a variable running_time to 0 Create a for loop that iterates 1000 times. In the body of the loop, Create an array of n random integers Get the time and set this to start-time. You will have to figure out what the appropriate command is in the programming language you are using to find the time Use bubble sort to sort the array Get the time and set this to end-time Subtract start-time from end-time and add the result to total_time Once the program has run, note The number of items sorted The average running time for each array (total_time/1000) Repeat the process six times, using 50, 250 and 500 as the size of the array for each of the two algorithms. 4. Repeat 3 using selection sort. 5. Create a spreadsheet showing the results of 3 and 4 and create a graph to graphically represent the information. Show both sort algorithms on the same graph for comparison. 6. Write a one page document explaining the results, bearing in mind that both algorithms have a complexity of O(n^2) and what you know about complexity analysis. Use your knowledge of complexity analysis to explain your results.

THIS IS THE ANSWER TO NUMBER 3 AND 4. PLEASE USE THIS TO ANSWER 5 AND 6***********************************

3.

import java.util.Random;
import java.util.Scanner;

public class Bubblesortiterations //Declare the class
{
public static void main(String args[]) //main method
{
Scanner sc = new Scanner(System.in); //Declare scanner class
System.out.print("Enter number: "); //Prompt and read the input size
int inputSize = sc.nextInt();
System.out.print("Enter number of iterations: ");

int num_iter = sc.nextInt();
int[] array = new int[inputSize]; //Create array of input size

Random rand = new Random(); //Create Random object
for(int i=0;i<inputSize;i++) //Generate the random value
{
array[i] = rand.nextInt(100);
}

System.out.println("Before Bubble sort"); //Print the random values before Bubble sort
for(int i=0;i<inputSize;i++) //Print the input array values
{
System.out.print(array[i]+" ");
}
System.out.println("\nSort the numbers using Bubble sort: ");
int temp,sortedcount = 0; //Declare local variables

long startTime = System.currentTimeMillis(); //Start the time

for (int c = 0 ; c < ( num_iter - 1 ); c++) //using two for-loops sort the input array
{
for (int d = 0 ; d < num_iter - c - 1; d++)
{
if (array[d] > array[d+1])
{
temp = array[d];
array[d] = array[d+1];
array[d+1] = temp;
sortedcount++;
}
}
}

long endTime = System.currentTimeMillis(); //End the time
long totalTime = endTime - startTime; //Compute the total time

System.out.println("Total iterations: "+num_iter); //Print the values
System.out.println("Total numbers sorted : "+sortedcount);
System.out.println("Total time taken: "+totalTime);
System.out.println("After Bubble sort");
for(int i=0;i<inputSize;i++){
System.out.print(array[i]+" ");
}
}
}

4.

import java.util.Random;
import java.util.Scanner;

public class SelectionSortIterations
{
public static void main(String args[]) //main method
{
Scanner sc = new Scanner(System.in); //Declare scanner class
System.out.print("Enter number: "); //Prompt and read the input size
int inputSize = sc.nextInt();
System.out.print("Enter number of iterations: ");
int num_iter = sc.nextInt();

int[] array = new int[inputSize]; //Create array of input size

Random rand = new Random(); //Create Random object
for(int i=0;i<inputSize;i++) //generate the random values
{
array[i] = rand.nextInt(100);
}
System.out.println("Before Selection sort"); //print the random values before Selection sort
for(int i=0;i<inputSize;i++) //print the input array values
{
System.out.print(array[i]+" ");
}
System.out.println("\nSort the numbers using Selection sort: "); //Print the header
int sortedcount = 0;
long startTime = System.currentTimeMillis();
for (int i = 0; i < num_iter-1; i++)
{
int min_index = i;
for (int temp = i+1; temp < inputSize; temp++)
if (array[temp] < array[min_index])
{
min_index = temp;
}

int temp = array[min_index]; // Swap the found minimum element with the first element
array[min_index] = array[i];
array[i] = temp;
sortedcount++;
}
long endTime = System.currentTimeMillis();
long totalTime = endTime - startTime;

System.out.println("Total iterations: "+num_iter); //print the values
System.out.println("Total numbers sorted : "+sortedcount);
System.out.println("Total time taken: "+totalTime);
for(int i=0;i<inputSize;i++)
{
System.out.print(array[i]+" ");
}
}
}

Need nano seconds, thanks.

Answer 1

Answer 5: Below are #1

1. Timings in nano seconds for both sorting algorithms

2. Output of the program

3. Chart for comparison

4. Configuration options from Excel

analysing the below Screen shots:

Answer 6.: Analyzing complexity for multiple runs of same program

below Screen shots analysing output

below following the cases

Analysis

1. Numbers of sorting average are varying because of the order of numbers in which they get input, in some case they will be closer to best case and in some cases closer to worst case.

2. Selection sort mostly out performs bubble sort because the number of swaps needed by the two algorithms (bubble sorts needs more swaps)

3. If we're dropping big-oh a little bit, bubble-sort really does do n^2 comparisons+possible swaps, but selection sort does (n^2 + n)/2, which is less than bubblesort for all n > 1