Algorithms

Question 1

Key techniques for Computational Thinking

Name the three techniques

Answer 1

1) Decomposition
2) Abstraction
3) Algorithmic thinking

Question 2

Decomposition

Define this term

Answer 2

Breaking down a complex problem into smaller problems and solving each one individually.

Question 3

Abstraction

Define this term

Answer 3

Picking out the important data from the problem, ignoring the data that doesn’t matter.

Question 4

Algorithmic Thinking

Define this term

Answer 4

A logical way of getting from the problem to the solution.

EXTRA:
If the steps you take to solve a problem follow an algorithm then they can be reused and adapted to solve similar problems in the future

Question 5

Algorithm

Define this term

Answer 5

A well-defined set of instructions for completing a specific task.

Question 6

Psuedo-code

Answer 6

1) Not an actual programming language but follows a similar structure and should read like one (roughly).
2) The idea is that it should clearly show an algorithm’s steps without worriying about the finer details and syntax
3) It is quick to write and easy to convert to a programming language
4) There are different ways to write it but it is correct so long as the person reading it understands how it works

Question 7

Flow Charts

Answer 7

Flow charts can represent algorithms and just like psuedo-code, there are different ways to write the same algorithm. They are represented using shapes.

Question 8

Start / Stop

Name the shape and function of this block

Answer 8

Start / Stop is shown by boxes with rounded corners.
These represent the beggining and end of the algorithm.

Question 9

Input / Output

Name the shape and function of this block

Answer 9

Inputs and Outputs are shown by parallelograms.
These represent anything that’s put into or taken out of the algorithm.

Question 10

Processes

Name the shape and function of this block

Answer 10

Processes are shown by rectangles.
These represent general instructions, processes and calculations.

Question 11

Decisions

Name the shape and function of this block

Answer 11

Decisions are shown by diamonds.
These represent decisions, often with a ‘yes’ or ‘no’ answer.

Question 12

Subroutine

Name the shape and function of this block

Answer 12

Subroutines are shown by rectangles that look like briefcases.
These represent references to other flowcharts, the flowchart’s function().

Question 13

Arrows

Name the function of this shape

Answer 13

**Arrows connect blocks and show the direction you should follow. **Some blocks might have multiple arrows coming in or going out of them.

Question 14

Search Algorithms

Name the 2 main search algorithms

Answer 14

1) Binary Search
2) Linear Search

Question 15

Binary search

Describe this search

Answer 15

A Binary Search looks for items in an Ordered List

Binary search works by looking for the middle of the list, checking if it is the item it is looking for, if not check if the item is in the side next to it and delete the group with no item in it.