Python 3.7:

1. Write a generator expression that repeats each character in a given string 4 times. i.e. given “gone”, every time you call the next method on the generator expression it will display “gggg”, then “oooo”, … etc and instantiate it to an object called G.  G = (…..) # generatorExpression object

2. Test and verify that iter(G) and G are the same things. What does this tell you about the nature of a Generator object/expression?

3. Assign Iter(G) to an iterator object called it1 and advance it to the next element by using next method.

4. Instantiate a new Iter(G) object called it2. Use the next method and advance it to the next element. Observe the result and compare it with the results of it1.

5. Does the new Iter(G) object start the iterator from the start of the string object? Write down your understanding/conclusion from this experiment.

6. How can you get back the Iter(G) to point back to the beginning of the string?

Write a java program creating an array of the numbers 1 through 10. Shuffle those numbers.

Randomly pick a number between one and ten and then sequentially search the array for that number.

Once the number is found, place that number at the top of the list.

Print the list. Perform #3 thru #5 ten times.

A. What can happen if pointer is uninitialized. Explain the concept and what should ideally be done
in such case

B. Memory was allocated initially for 5 elements, later on two more elements added to list. How can
space be managed in such case. Implement the scenario in C.

• What are some Linux Server operating system failover technologies? What about premium ones that you can pay for?
• What are some Windows Server operating system failover technologies? What about premium ones that you can pay for?
• Discuss the process for failover for both subjects you chose!

Consider the following three tables, primary and foreign keys.

Table Name        SalesPeople

Attribute Name                                Type                                      Key Type

EmployeeNumber             Number                               Primary Key

Name                                   Character

JobTitle                                  Character           

Address                                 Character

PhoneNumber                     Character

YearsInPosition                             Number

Table Name        ProductDescription

Attribute Name                                Type                                      Key Type

                ProductNumber                Number                               Primary Key

                ProductName                  Character           

                ProductPrice                   Number

Table Name        SalesOrder

Attribute Name                                Type                                      Key Type

                SalesOrderNumber        Number                               Primary Key

                ProductNumber               Number                               Foreign Key

                EmployeeNumber           Number                               Foreign Key

                SalesOrderDate                Date

Assume that you draw up a new sales order for each product sold.

Develop the following queries in SQL:

a.       All the Sales People with less than four years in position.

b.      All the Product Names sold on April 4^th.

c.       All the Products sold by Sales People less than 3 years in the position.

The program is not asking y/n :look below

Enter your grade:0.00
F
Continue (y/n)y
Enter your grade:3.33
B+
Enter your grade:
--------------------------------------------

def calci():
    grade = float(input("Enter your grade:"))
    while (grade <= 4):
        if (grade >= 0.00 and grade <= 0.67):
            print("F")
            break
        elif (grade >= 0.67 and grade <= 0.99):
            print("D-")
            break
        elif (grade >= 1.00 and grade <= 1.32):
            print("D")
            break
        elif (grade >= 1.33 and grade <= 1.66):
            print("D+")
            break
        elif (grade >= 1.67 and grade <= 1.99):
            print("C-")
            break
        elif (grade >= 2.00 and grade <= 2.32):
            print("C")
            break
        elif (grade >= 2.33 and grade <= 2.66):
            print("C+")
        elif (grade >= 2.67 and grade <= 2.99):
            print("B-")
            break
        elif (grade >= 3.00 and grade <= 3.32):
            print("B")
            break
        elif (grade >= 3.33 and grade <= 3.66):
            print("B+")
        elif (grade >= 3.67 and grade <= 3.99):
            print("A-")
            break
        elif (grade == 4.00):
            print("A")
            break
        elif (grade == 4.00):
            print("A+")
        else:
            print("Invalid input enter FLOAT only")
        calci()


def main2():
    question = input("Continue (y/n)")
    if question == "n" or question == "N":
        print("Bye")
    elif question == "y" or question == "Y":
        calci()
        main2()
    else:
        print("Invalid Input-Enter either y or n")
        main2()


print("ISQA 4900 quiz")
calci()
main2()
 fix the error

(Programming Language: Python)

It's trivial that the value of a number remains the same no matter how many zeros precede it. However, adding the zeros at the end of the number increases the value * 10. Jasmine is tired of seeing \001/100" on her tests (well yes, no one really writes 001, but Jasmine's teacher finds it funny to do so). So, she managed to login to her teacher's computer and now wants to design a function that can move the 0's in her grade to the end before her teacher uploads her grades. Although we don't agree with Jasmine's tactics, Krish (Jasmine's mentor) told us to help her out by finishing the `move zeros' function. This function should move all the 0's in the given list to the end while preserving the order of the other elements.

Remember that this function needs to modify the list, not return a new list!

---------------------------------------------

def move_zeros(lst: List[int]) -> None:

"""

Move all the 0's in lst to the END of the lst *in-place*, i.e. *modify* the list, DONT return a new list

>>> lst = [1, 0, 2, 3]

>>> move_zeros(lst)

>>> lst [1, 2, 3, 0]

"""

pass

Explain the bit-plain slicing ? Subject is digital image processing

1 Objective The purpose of this assignment is to test your familiarity with Java I/O, and if-else statements. Please submit your file as ”Shipping.java”

2 The Backstory Amazon.com wants to try out it’s new ‘Delivery by Drone” service and has recruited you to write a Java console application to calculate the shipping cost. They are going to charge the customer based on various criteria, as shown below:

Amazon Prime members get a 10% discount.

3 Specifications

• First, ask for the weight of the package (in kilograms). The user can enter this as a decimal number, so use type double. Values of 0 or less are invalid (i.e. a package has to weigh something). Do not accept weights of more than 20 Kg either, as this is the maximum weight the company will ship).

• If the user enters an invalid choice, print an appropriate error message and abort the program. (See sample outputs for error messages).

• Now ask the user to enter the distance to ship the package (in miles). This will be entered as an integer. 0 miles or less is considered invalid (must be a positive distance to ship). Also, do not accept distances of more than 3000 miles - consider 3000 miles to be the company’s maximum shipping distance.

• If the user enters an invalid choice, print an appropriate error message and abort the program. (See sample outputs for error messages).

• For a valid weight and distance, compute the shipping charges according to the chart above, noting that ”rate per 50 miles shipped” means that anything up to 50 miles is at the 50 mile rate, anything above 50 up to 100 miles is at the 100 mile rate, and so on.

• Ask if the user is an Amazon Prime member. If the user says Yes, give them a 10% discount.

• Print out the following results: – The package weight (default format), in kilograms. – The shipping rate for this package, to 2 decimal places, (money format). – The number of miles chosen. – The calculated shipping cost, to 2 decimal places (money format).

• See the Sample Runs below for expected output messages and numerical output formats.

• Also note: The System library has a method called exit(), which will cause a program to terminate immediately. It requires a parameter - usually, it is sufficient to just pass in the value 0

4 Sample Runs

Sample Run 1:

Welcome to Amazon Shipping Calculator

Please enter the weight of the package, in Kg: 19.4

Please enter the distance to be shipped (in miles): 2318 Are you an Amazon Prime member? (Yes/No): No

Package weight = 19.4 Kg Shipping rate = $40.60 per 50 miles Number of miles = 2318

Total shipping charges = $ 1908.20

Goodbye

Sample Run 2:

Welcome to Amazon Shipping Calculator

Please enter the weight of the package, in Kg: 8.4 Please enter the distance to be shipped (in miles): 134

Are you an Amazon Prime member? (Yes/No): Yes

Package weight = 8.4 Kg Shipping rate = $22.43 per 50 miles Number of miles = 134

Total shipping charges = $ 60.56

Goodbye

Sample Run 3 (error case): Welcome to Amazon Shipping Calculator

Please enter the weight of the package, in Kg: -5 Invalid package weight. Program aborted

Sample Run 4 (error case): Welcome to Amazon Shipping Calculator

Please enter the weight of the package, in Kg: 21.8 Cannot accept packages over 20 Kg. Program aborted

Replace <missing code> with your answer. Your code should approximate the value of π (~3.141592653589793). You can approximate pi using the following formula:

π = 4 * (1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11 + 1/13 - 1/15 + …)

For this problem, let n be the number of terms to add in the series. For example, if n = 5, your code should compute the following: 4 * (1 - 1/3 + 1/5 - 1/7 + 1/9). If n = 3, your code should compute 4 * (1 - 1/3 + 1/5)

public static void main(String[] args)
{
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();

int piApprox = <missing value>;

<missing code>

System.out.println("piApprox = " + piApprox);

}

What is a good website that uses visual organization and a very bad one. explain how each of the 4 principles (proximity, alignment, consistency, contrast) of visual organization are applied well or not applied.

Create a Java Program to calculate compound interest.

This can all be done in the main() method.

1. Create a double variable named currentBalance.
2. Create a double variable named newBalance.
3. Create a final double variable named INTEREST_RATE and assign 1.05 to it.
4. Create a int variable named yearCount.
5. Prompt for the "Number of years to invest" and store the input into the yearCount variable.
6. Prompt for the "Amount to Invest" and store this in the currentBalance variable.
7. Assign currentBalance to newBalance.
8. Using a 'FOR' loop, create and display the balance for each year. Additional variables may be required ( such as for the current year being displayed)
   1. newBalance= newBalance * INTEREST_RATE;
   2. Review the FOR loop example in Chapter 6 -Section 6.3 page 92
   3. Format the displayed balance to show 2 decimal places only.

Example:

Number of years to invest:5

Amount to Invest:1000

Year 1 balance =  1050.00
Year 2 balance =  1102.50
Year 3 balance =  1157.63
Year 4 balance =  1215.51
Year 5 balance =  1276.28


   Display the message "You have doubled your investment" and terminate the loop if/when you have more than doubled your initial investment.

please describe below technology used, benefit, issue and conclusion in your words

Technology Used

Encryption was almost exclusively used only by governments and large enterprises until the late 1970s when the Diffie-Hellman key exchange and RSA algorithms were first published -- and the first personal computers were introduced. By the mid-1990s, both public key and private key encryption were being routinely deployed in web browsers and servers to protect sensitive data.

Devices like modems, set-top boxes, smartcards and SIM cards all use encryption or rely on protocols like SSH, S/MIME, and SSL/TLS to encrypt sensitive data. Encryption is used to protect data in transit sent from all sorts of devices across all sorts of networks, not just the internet; every time someone uses an ATM or buys something online with a smartphone, makes a mobile phone call or presses a key fob to unlock a car, encryption is used to protect the information being relayed. Digital rights management systems which prevent unauthorized use or reproduction of copyrighted material, are yet another example of encryption protecting data. Cryptographic hash functions.

Encryption is usually a two-way function, meaning the same algorithm can be used to encrypt plaintext and decrypt ciphertext. A cryptographic hash function can be viewed as a type of one-way function for encryption, meaning the function output cannot easily be reversed to recover the original input. Hash functions are commonly used in many aspects of security to generate digital signatures and data integrity checks. They take an electronic file, message or block of data and generate a short digital fingerprint of the content called a message digest or hash value. The key properties of a secure cryptographic hash function are:Output length is small compared to input o Computation is fast and efficient for any input or Any change to input affects lots of output bits o One-way value -> the input cannot be determined from the output of Strong collision resistance -> two different inputs can't create the same output

The ciphers in hash functions are optimized for hashing: They use large keys and blocks, can efficiently change keys every block and have been designed and vetted for resistance to related-key attacks. General-purpose ciphers used for encryption tend to have different design goals. For example, the symmetric-key block cipher AES could also be used for generating hash values, but its key and block sizes make it nontrivial and inefficient.

Encryption helps protect business data. The technology comes in many forms, with key size and strength generally being the biggest differences in one variety from the next.

1. Triple DES:

Triple DES was designed to replace the original Data Encryption Standard (DES) algorithm, which hackers eventually learned to defeat with relative ease. At one time, Triple DES was the recommended standard and the most widely used symmetric algorithm in the industry.

Triple DES uses three individual keys with 56 bits each. The total key length adds up to 168 bits, but experts would argue that 112bits in key strength is more like it.

Despite slowly being phased out, Triple DES still manages to make a dependable hardware encryption solution for financial services and other industries.

2. RSA:

RSA is a public-key encryption algorithm. It also happens to be one of the methods used in our PGP and GPG programs.

Unlike Triple DES, RSA is considered an asymmetric algorithm due to its use of a pair of keys. You’ve got your public key, which is what we use to encrypt our message, and a private key to decrypt it. The result of RSA encryption is a huge that takes attackers quite a bit of time and processing power to break.

3. Blowfish:

Blowfish is another algorithm designed to replace DES. This symmetric cipher splits messages into blocks of 64 bits and encrypts them individually. Blowfish is known for both its speed and effectiveness as many claim that it has never been defeated. Vendors have taken full advantage of its free availability in the public domain. Blowfish can be found in software categories ranging from e-commerce platforms for securing payments to password management tools, where it used to protect passwords. It’s definitely one of the more flexible encryption methods available.

4. Twofish:

Keys used in this algorithm may be up to 256 bits in length and as a symmetric technique, only one key is needed. Twofish is regarded as one of the fastest of its kind, and ideal for use in both hardware and software environments. Like Blowfish, Twofish is freely available to anyone who wants to use it. Encryption programs such as PhotoEncrypt, GPG, and the popular open source software TrueCrypt are there.

5. AES:

The Advanced Encryption Standard is the algorithm trusted as the standard by the U.S. Government and numerous organizations. Although it is extremely efficient in 128-bit form, AES also uses keys of 192 and 256 bits for heavy duty encryption purposes. AES is largely considered impervious to all attacks, with the exception of brute force, which attempts to decipher messages using all possible combinations in the 128, 192, or 256bit cipher. Still, security experts believe that AES will eventually be hailed the de facto standard for encrypting data in the private sector.

                                                   Benefits of Encryption

The primary purpose of encryption is to protect the confidentiality of digital data stored on computer systems or transmitted via the internet or any other computer network. A number of organizations either recommend or require sensitive data to be encrypted in order to prevent unauthorized third parties or threat actors from accessing the data. For example, the Payment Card Industry Data Security Standard requires merchants to encrypt customers' payment card data when it is both stored at rest and transmitted across public networks.

Modern encryption algorithms also play a vital role in the security assurance of IT systems and communications as they can provide not only confidentiality, but also the following key elements of security:

• Authentication: the origin of a message can be verified.

• Integrity: proof that the contents of a message have not been changed since it was sent.

• Non repudiation: the sender of a message cannot deny sending the message.

                                                                Encryption Issues

Although it seems like common sense to use data encryption in business and other entities for security, many organizations are opposed to encrypting data because of some of the obstacles involved with doing so.

Like everything else, data encryption has its pros and cons and businesses must look at all of the considerations to make an informed decision about encryption.

Data Encryption :

• Encryption Keys: Without a doubt, data encryption is a monumental task for an IT specialist. The more data encryption keys there are the more difficult IT administrative tasks for maintaining all of the keys can be. If you lose the key to the encryption, you have lost the data associated with it.

• Expense: Data encryption can prove to be quite costly because the systems that maintain data encryption must have capacity and upgrades to perform such tasks. Without capable systems, the reduction of systems operations can be significantly compromised.

• Unrealistic Requirements: If an organization does not understand some of the restraints imposed by data encryption technology, it is easy to set unrealistic standards and requirement which could jeopardize data encryption security.

• Compatibility: Data encryption technology can be tricky when you are layering it with existing programs and applications. This can negatively impact routine operations within the system.

For any cipher, the most basic method of attack is brute force; trying each key until the right one is found. The length of the key determines the number of possible keys, hence the feasibility of this type of attack. Encryption strength is directly tied to key size, but as the key size increases so, too, do the resources required to perform the computation.

Alternative methods of breaking a cipher include side-channel attacks, which don't attack the actual cipher but the physical side effects of its implementation. An error in system design or execution can allow such attacks to succeed.

Attackers may also attempt to break a targeted cipher through cryptanalysis, the process of attempting to find a weakness in the cipher that can be exploited with a complexity less than a brute-force attack. The challenge of successfully attacking a cipher is easier if the cipher has any flaw. For example, there have been suspicions that interference from the National Security Agency (NSA) weakened the Data Encryption Standard algorithm, and following revelations from former NSA analyst and contractor Edward Snowden, many believe the NSA has attempted to subvert other cryptography standards and weaken encryption products.

                                                           Conclusion

Thus, network security is one of the most important factors to consider while working over the internet, Local Area Network or other method. It doesn't matter how small or big businesses. It is said that there is no network that is immune to all attacks, a stable, fast and efficient network security system is essential to protecting data. A good network security system helps reduce the risk of data theft and sabotage. This analysis shows that AES is the better algorithm and AES does not have any well known weak points so far.