2.1 Algorithms

Question 1

What are the 3 principles of computational thinking?

Answer 1

• Decomposition
• Abstraction
• Algorithmic thinking

Question 2

What is an algorithm?

Answer 2

A sequence of instructions that perform a specific task when followed.

Question 3

What does decomposition mean?

Answer 3

Breaking down a large problem into smaller ones that can be solved individually.

Question 4

What does abstraction mean?

Answer 4

picking out the important piece of information and ignoring the details that don’t matter

Question 5

What does algorithmic thinking mean?

Answer 5

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

Question 6

What does the rounded rectangle mean in a flowchart?

Answer 6

Start/stop

Question 7

What does the parallelogram mean in a flowchart?

Answer 7

input/output

Question 8

What does the rectangle mean in a flowchart?

Answer 8

processes - general instruction, processes and calculations

Question 9

What does the diamond mean in a flowchart?

Answer 9

Decisions (yes and no)

Question 10

What does the arrow show in a flowchart?

Answer 10

The direction of the flowchart.

Question 11

What is a sub program?

Answer 11

Makes reference to another flowchart.

Question 12

What are the 2 types of searching algorithms?

Answer 12

Binary and linear search.

Question 13

What are the steps of linear search?

Answer 13

1) look at the first item in the unordered list
2) If that is the requested item then stop
3) if not look at the next item
4) repeat until you find the requested item in the list.

Question 14

What are the steps of binary search?

Answer 14

1) find the middle value
2) if that is the item then stop
3) if not then compare the item that you are looking for to the middle one and get rid of the irrelevant side.
4) do this until the item is found.

Question 15

In order to do a binary search, what does the list need to be?

Answer 15

The list has to be ordered

Question 16

What is the steps of a bubble sort?

Answer 16

1) start at the beginning of the list.
2) Compare the first value in the list with the next one up. If the first value is bigger, swap the positions of the two vales
3) Move to the second value in the list
4) Keep going until there are no more items to compare
5) Go back to the start of the list.

Question 17

What is the steps of insertion sort?

Answer 17

1) Look at the second item of the list
2) Compare it to all the items before it and insert the number into the right place.
3) Repeat steps 2 for the following items until the last number in the list is in the right place.

Question 18

What is the steps of Merge sort?

Answer 18

1) split the list in 2) keep on splitting the the list until there is one item
3) first merge the halved sub lists in order
4) then merge of the sub list together into order.