Software Engineering

Question 1

Steps Software Test Life Cycle (4 steps)

Answer 1

Unit Testing (verification)
Integration Testing (verification)
System Testing (validation)
Acceptance Testing (validation)

Question 2

Unit Testing

Answer 2

Evaluate individual components (e.g. functions or classes)

Question 3

Integration Testing

Answer 3

• test individual comonents (2 or more) of the system as a collective group.
• To identify problems in the interface between modules and functions.

Question 4

System Testing

Answer 4

• test if collective group of integrated components performs optimally
• to see if system fullfills quality standards.
• to see if system complies with all major requirements.

Question 5

Acceptance Testing

Answer 5

• to evaluate if system is ready for release

- test can the application perform all the specified functions

Question 6

What are the four pillars of Object Oriented Programming ?

Answer 6

Encapsulation/Privatisation
Abstraction
Inheritance
Polymorphism

Question 7

Encapsulation/Privatisation

Answer 7

• private class variables
• can only be accesed by public functions of this class
• restricting access, security, protection, avoid bugs through overrinding variable somewhere else
• code is easily readable if variables clearly belong to a class
• code is easily usable if we only need to access the functions and not the inner state of a class

Question 8

Abstraction

Answer 8

• hide away some of the implementation details
• e.g. in a function or class
• easily usable
• easily understandable code
• reusable, maintainable
• can be achieved through encapsulation
  (Coffee machine example)

Question 9

Inheritance

Answer 9

• class can inherit the properties and methods of another class
• reusability, maintainability
  (example cars)

Question 10

Polymorphism

Answer 10

• appearing in different forms
• we have the same function, which can be overriden and customized to an inherriting class
• e.g. every car makes an individual sound - which is then printed
• handle different data types

Question 11

Manifesto of agile software development

Answer 11

• Individuals and interactions over processes and tools
• Working software over comprehensive documentation
• Customer collaboration over contract negotiation
• Responding to change over following a plan

Question 12

Big O nested Loop?

Answer 12

O(N^2)

Question 13

Big O linear search ?

Answer 13

O(N) - look at every item if we search for item N

Question 14

Big O of two loops after one another ?

Answer 14

O(N) - one loop is O(N)

Question 15

How to determine Big O of an algorithm ?

Answer 15

Biggest O in the algorithm counts (e.g. O(N^2))

Question 16

List 8 common Big O’s ?

Answer 16

• O(1): constant time
• O(log n): logarithmic time
• O(n): Linear time
• O(n log n): linearithmic time
• O(n^2): quadratic time
• O(n^3): cubic time
• O(a^n): exponential time
• O(n!): factorial time

Question 17

What is Big O?

Answer 17

analyzes the running time of an algorithm depending on the input size

Question 18

Constant-time algorithm

Answer 18

• O(1)
• runs in a constant time no matter how long the input is
• e.g. programms without input
• e.g. checking the first byte of a file (length of file is not important)