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Cards in this deck (14)
- 1What is problem recognition ?Identify there is a problem to be solved // what the problem is.
- 2What is problem decomposition ?Splitting down a problem into sub-problems.
- 3Examples of computational methods ?> Divide and conquer
> Abstraction
> Critical thinking
> Visualisation
> Backtracking
> Heuristics
> Modelling
> Concurrency - 4What is data mining ?Turning large quantities of data into useful information.
Finding patterns within large quantities of
information. - 5What is performance modelling ?Simulate / test the behaviour of the system before it is used.
- 6Difference between graph and tree ?> Graph can be weighted
> Tree has a root
> A tree has a hierarchy (e.g. Parent/Child)
> A graph can be directed/undirected
> A graph has cycles - 7Advantages of visualisations ?> Visualisations benefit humans rather than computers
> Visualisations present the information in a simpler form to understand
> Visualisations can best explain complex situations - 8Compare the performance of Dijkstra’s algorithm and the A* search algorithm ?> Heuristic helps produce a solution in a faster time
> A* uses estimated distance from final node
> Dijkstra uses a weight/distance
> A* chooses which path to take next based on lowest current distance travelled
> Taking the shorter route A-B-E-I before exploring nodes from D and E
> Description of the different number of comparisons
that would be needed in this problem
> A* doesn’t need to find all possible solutions (saves time)
> Small-scale problem
> Quick to find a solution using either method
> Difference in programming complexity is minimal
> Don’t know if this problem needs to scale
> Most efficient route needed - 9Describe features of an IDE that help debug the program ?> Underlines syntax errors dynamically / Can be corrected before running / saves times
> Watch window / View how variables change during running of the program
> Break points / Stop the program at set points to check the values of variables
> Error message list / Tells you where errors are and suggests corrections
> Step-mode / Executes program one statement at a time to watch variable values and program pathways
> Traces / Print-outs of variable values for each statement - 10Parameters can be used to reduce the use of global variables. Compare the use of parameters to global variables in recursive functions ? > Parameter allows a value to be sent to a subprogram
> Global variables can be accessed throughout the scope of the program
> Local variables can only be accessed within the scope of the sub-program it's defined within – a parameter becomes a local variable in the function
> If global, equivalent of by reference -value would be over-ridden
> Global variable takes more memory than a local variable/parameter
> In recursion, each call produces a new local variable for num1
> Global would require altering the algorithm as the value would be over-ridden on each call
> Global would mean that memory space is kept throughout the running of the program, not just the sub-program
> Parameter enables memory to be reallocated
> Many more memory spaces needed for parameter - 11Explain why recursive algorithms uses more memory than iterative algorithms ?> Each recursive call stores the current state on the stack / creates new variables
> Iteration reuses the same variables - 12Describe the stages of a binary search on an array of size n ?> Repeat
> Calculating an array midpoint…
> …by adding the array lower bound to the array upper bound, dividing by 2 and rounding
> Compare array midpoint with value to search for…
> …if equal set found flag to true
> …if array midpoint < value to search for, change lowerbound to equal midpoint + 1
> …if array midpoint > value to search for, change upperbound to equal midpoint – 1
> Until lowerbound is greater than or equal to upperbound
> Return/output found flag - 13Explain the similarities and differences between a record and a class ?> Record is a data structure…
> …A class is a template for making data structures (objects)
> Class also has methods (which describes functionality)
> Both store data of different types
> Which can be accessed by their names
> But classes can make them accessible via methods
> Both can have multiple ‘instances’
> Class can include visibility of properties / private - 14Define the term ‘queue’ ?> A data structure
> FIFO (first in first out)
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- Flashcards on Untitled, created by Hamza Shehzad on 22/12/2020.
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- Hamza Shehzad
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