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2.1 Algorithms

5 dot points across 5 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

What are abstraction, decomposition and algorithmic thinking, and how do they help you solve a problem?

The principles of computational thinking: abstraction, decomposition and algorithmic thinking, and how each is used to analyse a problem and design a solution.
An OCR J277 2.1.1 answer on the principles of computational thinking: abstraction (removing unnecessary detail), decomposition (breaking a problem into smaller parts) and algorithmic thinking (a clear sequence of steps), with examples of how each is applied to a problem.
9 min answer →

How do you design and present an algorithm using pseudocode and flowcharts?

Producing algorithms using pseudocode and flowcharts to solve a problem, identifying the inputs, processes and outputs, and interpreting, correcting and refining algorithms others have written.
An OCR J277 2.1.2 answer on designing algorithms with pseudocode and flowcharts: identifying inputs, processes and outputs, the OCR Exam Reference Language, the standard flowchart symbols, and interpreting, correcting and refining algorithms.
11 min answer →

How do linear search and binary search work, and when is each one appropriate?

Standard searching algorithms: linear search and binary search, how each works step by step, the requirement that binary search needs a sorted list, and the comparison of their efficiency.
An OCR J277 2.1.3 answer on the two standard searching algorithms: how linear search and binary search work step by step, why binary search needs a sorted list, and how their efficiency compares.
10 min answer →

How do bubble sort, insertion sort and merge sort each put a list in order?

Standard sorting algorithms: bubble sort, insertion sort and merge sort, how each works step by step, and how they compare in approach and efficiency.
An OCR J277 2.1.3 answer on the three standard sorting algorithms: how bubble sort, insertion sort and merge sort each put a list in order step by step, and how they compare in method and efficiency.
12 min answer →

How do you use a trace table to work through an algorithm and find its output or its purpose?

Using trace tables to determine the output of an algorithm and to follow how the values of variables change, and determining the purpose of a simple algorithm.
An OCR J277 2.1.2 answer on using trace tables to follow an algorithm step by step, record how variable values change, find the output, and determine the purpose of a simple algorithm.
10 min answer →