Download Computational Thinking Concepts and more Quizzes Computer Science in PDF only on Docsity!
2.1 Computational thinking
Q
Abstraction A Simplifying a problem by only taking into consideration the necessary details required to obtain a solution leaving a representation without any unecessary details 2 Q Data abstraction A details about how data is being stored are hidden 3 Q Graph theory A A branch of paths that can be used to abstractly represent problems using a collection of nodes connected by edges 4 Q Caching A The temporary storage of data by the system in cache or memory for the benefit of faster retrieval if it is needed again in future
Q
Inputs A Any information relevant to the problem that is required by the system for processing 6 Q Outputs A The result returned by a system for a given input after running the entire process or part of a process 7 Q Preconditions A A perquisite or state of a system and its surroundings required to run a use case and return a valid solution 8 Q Reusable program components A Components that have already been written, debugged and tested that can be transplanted into new systems to save development time in project completion 9
Q
Concurrent processing A Processing where the system appears to perform multiple tasks simultaneously 14 Q What is abstraction by generalisation A grouping together similarities within a problem to identify what kind of problem it is where a common solution can be used to solve these problems 15 Q How does procedural abstraction work A It models what a subroutine does without considering how this is done. Once a procedure has been coded, it can be reused as a black-box 16 Q What do large problems make use of in relation to abstraction A multiple levels of abstraction, where each level performs a different role 17
Q
What are the highest levels of abstraction when multiple are used A closest to the user and are usually responsible for providing an interface for the user to interact with hardware 18 Q What are the hlowest levels of abstraction when multiple are used A e lowest levels of abstraction are responsible for actually performing these tasks through the execution of machine code. 19 Q TCP ip model abstraction A abstraction for how networks function, separated into four layers of abstraction 20 Q Do each layer in the TCP IP model need to know how the others work A No 21
Q
Inputs? A Any data that is required to solve a problem, usually entered into the system by the user 26 Q Outputs? A The results that are passed back once the inputs have been processed and the problem solved 27 Q What considerations do programmers need to make about inputs and outputs when thinking ahead? A Method of input/output (device used) Data structures used Data types used Order of data 28 Q You must be able to extract inputs and outputs from a real world scenario… Book reservation system, e.g. at a library? Study These Flashcards
A
Inputs - Book details: name, author, ISBN, Borrower details: name, library card number, Collection point Outputs - Expected waiting time, Confirmation, Availability at other libraries 29 Q What are preconditions? Study These Flashcards A Requirements which must be met before a program can be executed 30 Q Where can preconditions be defined? Study These Flashcards A Within the code or within documentation 31 Q Where are preconditions required? Study These Flashcards A Stack functions - check stack isn’t empty when popping an element from a stack, or is full when pushing an element onto the stack Factorial function - the number passed to the function cannot be negative
Q
What are the advantages of caching web pages? Study These Flashcards A Content can be loaded without delay images and text do not have to be downloaded again multiple times Frees bandwidth for other tasks on a network Less time is spent wasting 36 Q What is the name given to the technique in which algorithms are used to predict which instructions are likely to soon be used? Study These Flashcards A Prefetching 37 Q What are the limitations of caching? Study These Flashcards A Accuracy of the algorithm used Effectiveness of algorithm in managing the cache Size of the cache 38 Q What are the advantages of reusable components?
Study These Flashcards A More reliable than new components, as they have already been tested As developing from scratch is not required, this saves time, money and resources 39 Q What are some examples of reusable components? Study These Flashcards A Abstract data structures e.g. queues and stacks Classes Subroutine 40 Q What are the limitations of using reusable components? Study These Flashcards A Compatibility issues with the rest of the software Causing to be more costly and time-consuming then developing them in-house 41 Q What is the first stage of thinking procedurally? Study These Flashcards A
Study These Flashcards A Problems can be solved and modules developed by different people Tasks can be tested separately, modules are self-contained 46 Q What sort of problems is top-down design suited to? Study These Flashcards A Large, complex problems 47 Q What is the second stage of thinking procedurally in software development? Study These Flashcards A Identifying components of a solution 48 Q How can the lowest level subproblems in top-down design in code? Study These Flashcards A As self-contained modules or subroutines 49 Q
What do software developers need to consider when recombing components of a solution? Study These Flashcards A The order in which subroutines are executed, and how they interact with each other, based on their role in solving the problem 50 Q What must a software developer do before designing a subroutine to solve a particular problem? Study These Flashcards A See whether it is possible for an already existing subroutine or module to be used 51 Q What are the advantages of utilising reusable components? Study These Flashcards A More reliable than newly-coded components, as they have already been tested This saves time, money and resources 52 Q What is a decision? Study These Flashcards A A result reached after consideration.
By evaluating the importance of different factors and selecting options which satisfy the needs of the task the most appropriately 57 Q Does the result of a decision affect the flow of the program? Study These Flashcards A The program will follow a different route depending on the decision made by the user 58 Q What is concurrent thinking? Study These Flashcards A It is completing more than one task at any given time 59 Q Are concurrent processing and concurrent thinking the same thing? Study These Flashcards A No, one uses computer processors, one uses the human brain 60 Q What is parallel processing?
Study These Flashcards A Completing multiple tasks simultaneously at any given time 61 Q What is concurrent processing? Study These Flashcards A Giving a slice of processor time to tasks to give the illusion of parallel processing 62 Q What are the benefits of concurrent processing? Study These Flashcards A More tasks can be completed in a given time Other tasks can be completed while waiting for an input/user interaction 63 Q What are the drawbacks of concurrent processing? Study These Flashcards A If lots of users are requesting for tasks to be completed, it takes longer for everyone to complete their task 64
