03. Introduction to Algorithms

Learning Outcomes

You will learn to:

Describe the decomposition of a problem

Describe what an algorithm is

Describe Psuedocode

Describe flowchart and flowchart shapes

Write a simple algorithm to calculate the area of a circle.

Resource

One of the best resources is the teach-ICT.com site.  Please use the following link:

http://www.teach-ict.com/gcse_computing/ocr/216_programming/algorithms/miniweb

Definition

An algorithm is simply a set of instructions for performing a task. Some algorithms are more efficient than others and we will look at these in more detail later in the course.  The purpose of an algorithm is to find a solution to a problem of to complete a goal in the most efficient and effective way possible.  A program is a set of instructions which have been written in a lNguage the computer understands in order to make the algorithm work.

Decomposition

The reason for introducing this topic now is that in order to program well you are going to need to think like a computer - particularly when you do your controlled assessment.  You need to decompose or break tasks down into small chunks so that they are easy to follow and impossible to get wrong.

Penalty Kick Algorithm

Look at the following algorithm for taking a penalty kick.  Try to work out what is wrong with it.  Remember the objective of a penalty kick is obviously to score a goal.

1. Start

2. Place football on penalty spot

3. Kick ball

4. End

TASK 1

In pairs write an algorithm for taking a penalty kick which will result in a goal being scored.

Lift Algorithm

Look at the following algorithm and work out why this one achieves all it's objectives efficiently and effectively:

1. Start

2. Wait until doors are closed

3. Wait until the floor button is pressed

  If button pressed is > than current floor

     Move lift upwards

  If button pressed is < than current floor

     Move lift downwards

4. When current floor = button pressed

5.  Open doors

6. End

TASK 2

Write an algorithm to calculate the area of a circle.

Flowcharts

Now let's explore the teach-ICT.com pages on Flowcharts

http://www.teach-ict.com/gcse_computing/ocr/216_programming/algorithms/miniweb/pg7.htm

Homework

Select either your algorithm for calculating the area of a circle or the lift operation algorithm in recreate as a flowchart.

June 19th

STARTER

In your exercise books complete the following:

1. Express 23 as a Hex?
2. Express 23 as an 8 bit binary?
3. Express 123 as a Hex?
4. Express 123 as an 8 bit binary?
5. Express 10100011 as a Hex?
6. Express 11101011 as a Hex?
7. Express 10101011 as a Hex?
8. Express 11101011 as a Hex?
9. Express 11100111 as a Hex?
10. Express 11111011 as a denary?

Tip: for questions 5-9 split into two nibbles and show working.

Work through the SQL TUTORIAL –

1.       Practise each example in the simulator

2.       In your exercise books make a note of the key word syntax.

YOU SHOULD AIM TO FINISH THE WHOLE COURSE – HOWEVER IN TODAY'S 

LESSON MAKE SURE THAT YOU GET AS FAR AS CHAPTER ABOUT 'DELETE'.

Home

http://www.w3schools.com/sql/default.asp

Intro

http://www.w3schools.com/sql/sql_intro.asp

Syntax

http://www.w3schools.com/sql/sql_syntax.asp

Select

http://www.w3schools.com/sql/sql_select.asp

Distinct

http://www.w3schools.com/sql/sql_distinct.asp

Where

http://www.w3schools.com/sql/sql_where.asp

AND & OR

http://www.w3schools.com/sql/sql_and_or.asp

ORDER BY

http://www.w3schools.com/sql/sql_orderby.asp

INSERT

http://www.w3schools.com/sql/sql_insert.asp

Update

http://www.w3schools.com/sql/sql_update.asp

Delete

http://www.w3schools.com/sql/sql_delete.asp

June 18th

HOMEWORK AJT DUE 22nd June

Ensure that you have complete the SQL course up to DELETE

DATA VALIDATION

On BBC Bite Size complete the following:

http://www.bbc.co.uk/education/guides/zdvrd2p/revision

Watch the video

http://www.bbc.co.uk/education/guides/zdvrd2p/activity

Complete the test

http://www.bbc.co.uk/education/guides/zdvrd2p/activity

n.b. Repeat until you get all correct – note your answers.

As a reply to this post provide definitions with examples  of the following:

- Presence check

-  Range Check

- Picture check 

-  Type check

ALSO, IF YOU HAVE NOT ALREADY COMPLETED THE CHALLENGES FROM TODAY'S LESSON THESE MUST BE DONE FOR HOMEWORK.

STARTER

• Express 11001101 as DENARY
•   Express 233 as BINARY
•     Express 233 as HEX
•     Express 167 as HEX

SHOW YOUR WORKING

1.       First let’s finish our notes from Teach-ICT.com

http://www.teach-ict.com/as_as_computing/ocr/H447/F453/3_3_9/sqlintro/miniweb/pg5.htm

CHALLENGE 1

The two tables Product and Supplier form a relational database used by a shoe shop.

(a)    State the primary key of the Supplier table and justify your choice.  (2) 

(b)   List the results of executing the following SQL query on the database above. (4)

SELECT Product.Name, Product.Quantity, Supplier.PostCode

FROM Product, Supplier WHERE Product.Quantity > 40 AND Supplier.Name = ‘Trainers4Us’

AND Product.SupplierCode = Supplier.SupplierCode 

(c)    Write an SQL statement to add the following data to the Product table:  (3)

444AA  Slippers  6.99  32  100  

CHALLENGE 2

(a)    Look at the Products table. Write an SQL statement that orders the products alphabetically by supplier name (3)

(b)   Look at the Products table. Write an SQL statement that orders the by the quantity with the largest first? (3)

Representation of Character

In your books do the following:

(1) Find an ASCII table

(2) How many bytes does an ASCII table take up?

(3) What does ACII mean?

(4) What is ASCII used for?

(3) What is 'D' as a denary in ASCII?

(4) What is 'g' as a denary in ASCII?

(5) List all the differences between ASCII and UNICODE

(6) How many bytes does Unicode take up?

(7) How many characters can UNICODE display?

(8) Why do we need UNICODE?

HOMEWORK

By a reply to this post write up some research on QUANTUM COMPUTING.  Answer the following:

What is Quantum Computing?
How does it work?
What is it used for?
What are its advantages?
What are its disadvantages?
How can it help change the world?

BIG QUESTIONS - BUT REMEMBER CUTTING AND PASTING IS A WASTE OF TIME!

SQL

SQL

STARTER COMPLETE THE QUIZ

http://www.w3schools.com/quiztest/quiztest.asp?qtest=SQL

How many did you get?

DEFINITION

Find and write down a definition of SQL.  What is it used for?

BASIC SYNTAX

Write the basic keywords in your notebook:

http://www.teach-ict.com/gcse_computing/ocr/databases/concepts/miniweb/pg9.htm

PRACTICSE

Now let’s practise using the w3schools site – let’s go through the first four chapters:

REVISION FOR MOCK EXAM

REVISION FOR SUMMER 2015 MOCK EXAM

Units of storage

http://www.teach-ict.com/gcse_computing/ocr/214_representing_data/units/miniweb/index.htm

Numbers

http://www.teach-ict.com/gcse_computing/ocr/214_representing_data/number/miniweb/index.htm

Characters

http://www.teach-ict.com/gcse_computing/ocr/214_representing_data/character/miniweb/index.htm

Instructions

http://www.teach-ict.com/gcse_computing/ocr/214_representing_data/instructions/miniweb/index.htm

Networks and their advantages (Why network?)

http://www.teach-ict.com/gcse_computing/ocr/215_communications_networking/networks/miniweb/index.htm

Network Topologies

http://www.teach-ict.com/gcse_computing/ocr/215_communications_networking/network_topologies/theory_network_topologies.html

Network Protocols (Encryption)

http://www.teach-ict.com/gcse_computing/ocr/215_communications_networking/network_topologies/theory_network_topologies.html

http://www.teach-ict.com/technology_explained/encryption/encryption.html

SQL

http://www.teach-ict.com/as_as_computing/ocr/H447/F453/3_3_9/sqlintro/miniweb/index.htm

http://www.teach-ict.com/gcse_computing/ocr/databases/concepts/miniweb/pg9.htm

http://www.w3schools.com/sql/default.asp

Data Validation

http://www.teach-ict.com/gcse_computing/ocr/databases/validating/miniweb/index.htm

Quantum Computing

https://www.youtube.com/watch?v=g_IaVepNDT4

http://whatis.techtarget.com/definition/quantum-computer

June 8th Database Activities

Databases Reprise

In this section we are going to reprise our work on databases.

Look at the table below:

The table below contains details of animals at a zoo and the enclosure they live in.

Zoo

ID	Name	Breed	Gender	Date_Of_Birth	Enclosure	Capacity	Headkeeper
C009	Terry	Lion	Male	30/6/1982	Big Cats	12	J Milner
A002	Maria	Chimpanzee	Female	12/3/2012	Ape House	50	S Larkin
A019	Sam	Gibbon	Female	10/6/2002	Ape House	50	S Larkin
C015	Toni	Tiger	Female	18/6/2009	Big Cats	12	J Milner
B033		Red deer	Female	6/7/2007	Deer Park	200	A Hunt
A007	Charlie	Chimpanzee	Male	19/7/2011	Ape House	50	S Larkin

Re-organise the data into two linked tables called Animal and Enclosure.

Animal

Enclosure

HOMEWORK

The table below is called PlayList and it lists some of the songs on five albums of children’s songs.

PlayList

Album_Title	Artist	Released	Genre	Track_No	Song_Title	Time
In The Night Garden – A Musical Journey	Andrew Davenport	2007	Children’s music	3	Hello Igglepiggle!	0:38
In The Night Garden – A Musical Journey	Andrew Davenport	2007	Children’s music	12	Catch Makka Pakka’s Og-pog!	7:32
In The Night Garden – A Musical Journey	Andrew Davenport	2007	Children’s music	16	The Pinky Ponk	1:09
Heads, Shoulders, Knees & Toes	The C.R.S. Players	2004	Children’s music	1	Hokey Cokey	2:28
Heads, Shoulders, Knees & Toes	The C.R.S. Players	2004	Children’s music	12	Ten Green Bottles	2:33
50 Nursery Rhyme Songs	Countdown Kids	2009	Children’s music	1	Old MacDonald Had a farm	2:03
50 Nursery Rhyme Songs	Countdown Kids	2009	Children’s music	3	This Little Pig	1:13
50 Nursery Rhyme Songs	Countdown Kids	2009	Children’s music	12	Six Little Ducks	1:02
CBeebies the Album	Various Artists	2012	Children’s music	5	My Name is	1:21
CBeebies the Album	Various Artists	2012	Children’s music	12	Everything’s Rosie Theme Tune	0:43
CBeebies the Album	Various Artists	2012	Children’s music	21	Summer Song	1:54
Children’s Party Time	Kid’s Players	1995	Children’s music	12	The Birdie Song	2:23

·           Reorganise the data in the table above into two linked tables called Album and Song.

·           Describe how the relationship between the two tables (Album and Song) is created.

·           Give the number of fields and records in the Album table and in the Song table.