3.1 - algorithm/efficiency

Question 1

define decomposition

Answer 1

the process of breaking down a complex problem to smaller sub-problems and solving them individually

Question 2

define abstraction

Answer 2

Removing unnecessary detail from a problem

Question 3

define an algorithm

Answer 3

a sequence of steps which are carried out in order to solve a problem

Question 4

what are the benefits of decomposition and abstraction?

Answer 4

easier to solve a problem

Question 5

what data type is able to store the following data?

100, 1, 3

Answer 5

Integer

Question 6

give an example of decomposition in real life

Answer 6

process of making a car

• making the engine
• making the wheels

Question 7

give an example of abstraction

Answer 7

not focusing on the additional paths on an underground map

Question 8

what is generalisation

Answer 8

the process of creating one solution to a problem, which can then solve many different problems

Question 9

define algorithmic thinking

Answer 9

the ability to be able to solve problems by creating algorithms

Question 10

what is functional decomposition

Answer 10

splitting up a problem into smaller problems, each would be programmed using subroutines

Question 11

what is selection

Answer 11

the ability to run different parts of the algorithm based on a condition

Question 12

what are parameters

Answer 12

limits of the inputs in an algorithm

Question 13

what is a dry run of a pseudocode?

Answer 13

when a code is run by programmers instead of computers

Question 14

what are the advantages of dry runs

Answer 14

being able to see where logical errors and bugs are

Question 15

what is the purpose of a trace table?

Answer 15

To show the value of each variable while an algorithm is dry run

Question 16

Is a computer program an algorithm?

Answer 16

It is an implemention of an algorithm, not an algorithm itself

Question 17

Define pseudo code?

Answer 17

A text based way of setting out an algorithm

Question 18

What is casting?

Answer 18

The process of declaring the data type to be used (when assigning to a variable)

Ie. Phone

Question 19

Give examples of iteration in a code?

Answer 19

• WHILE
• FOR
• DO

(Running the same code repeatedly)

Question 20

Give two ways to measure the efficiency of an algorithm?

Answer 20

• measure the time taken

- measure the space used

Question 21

If you measure the time efficiency, what do you measure?

- TAKE A PAUSE, THINK ABOUT IT

Answer 21

The number of steps in the algorithm (not time taken to complete)

🐾🐾🐾🐾🐾

Question 22

Disadvantage of writing efficient algorithms?

Answer 22

• efficient algorithms can be more complicated + hard to code than non-efficient ones
• may need other requirements (ie. binary search only works on ordered lists)

Question 23

What is a computer program an implementation of?

Answer 23

Implementation of an algorithm

ALGORITHM IS NOT A COMPUTER PROGRAM

Question 24

what does it mean if something is language independent?

Answer 24

means an algorithm can be written in any programming language