Section 10 Computational Thinking

Different methods of Designing Algorithms

• Flow charts : A diagram of the sequence of movements or actions of people or things involved in a complex system or activity.
  
• Pseudocode: is an informal, high-level description of a computer program or algorithm, often using natural language mixed with basic programming concepts to outline functionality and logic without strict syntax.
  
  

Thinking Currently

• Concurrent computing: Concurrent computing is a form of computing in which several computations are executed concurrently—during overlapping time periods—instead of sequentially—with one completing before the next starts.
• Parrallel computing: Parallel computing is a type of computation in which many calculations or processes are carried out simultaneously
• Current Processing: takes place when several processes are running, with each in turn being given a slice of processor time. This gives the appearance that several tasks are being performed simultaneously, even though only one processor is being used.

Advantages of Current Processing

• Increased program throughput
• Time that would be wasted by the processor waiting for the user to input data or look at output is used on another task

Disadvantages of Current Processing

• If a large number of users are all trying to run programs, and some of these involve a lot of computation, these programs wil take longer to complete

Advantages of Parallel Processing

• Enable several tasks to be performed simultaneously by different processors. It can speed up processing enormously when repetitive calculations need to be performed on large amounts of data
• Graphics processors can quickly render a3-D object by working simultaneously on individual components of the graphic

Disadvantages of Parallel Processing

• parallel processing has limitations; there is an overhead in coordinating the processors and some tasks may run faster with a single processor than with multiple processors.

Methods of Problem Solving

• Enumeration - Listing all cases
• Simulation - is the process of designing a model of a real system in order to understand the behaviour of the system
• Theoretical Approach -
  • Divide and Conquer - divide and conquer is an algorithm design paradigm. A divide-and-conquer algorithm recursively breaks down a problem into two or more sub-problems of the same or related type, until these become simple enough to be solved directly.
  • Problem Abstraction(shown through images)
    Normal:
    
    Abstracted:
    

Visualisation

• Visualistion is the use of interactive, sensory representations, typically visual, of abstract data to reinforce cognition, hypothesis building, and reasoning.

Backtracking

• Backtracking is a method of trying out different sequences until you come accorss that leads you to the solution
• When you would use backtracking:
  • You dont have enough info to know which is the best route
  • Each decision leads to a new set of choices
  • Depth Searching a graph