Revision

• Computer Science
• Secondary Education

Revision

What is the correct version of code?

1. print("Hello World")
2. print"(Hello World")
3. print((Hello World))
4. print(Hello World")

What would the output be for this code?

myname = "bob"
name = input("please enter your name: ")
print(myname)

1. bob
2. name
3. john
4. myname

What would the output be for this code?

food = "pizza"
print("orange")

1. print pizza
2. food
3. orange
4. pizza

What is programming?

1. The order in which we write our code.
2. The programs we use.
3. A set of instructions to complete a task.
4. The result of our program when run.

What is sequencing?

1. A set of instructions.
2. A set of instructions in order.
3. A program created by code.
4. The result of our program when run.

Quiz should take 3-4 mins, allow time on later questions for students to read through the code options to figure out which option is correct. 

To review the concepts of Programming

I feel confident in answering questions about computer programming

 Variable

A variable is a named storage location in a computer's memory that can hold a value. The value stored in a variable can be changed throughout the program's execution, hence the term "Variable".

Variables 

• In programming, a variable is like a container that holds a piece of information. This information can be anything, like a number, a word, or even a whole sentence!

• For example, imagine you have a box that can hold a piece of fruit. You can put an apple in the box, and then later on, you can take the apple out and look at it. In programming, a variable is like that box. You can put information into the variable, and then you can use that information later on in your program.

• To use a variable, you first need to give it a name. This is like labelling the box with the word "apple" so you know what's inside. In programming, you can choose any name you want for your variable, as long as it follows certain rules. For example, the name can't have spaces in it, and it can't start with a number.

Task 3 - Variables

We are now going to create a variable and then save some data to it. We will then output "print" this data to the screen.

Press the green play button to execute the code.

Task 4 : Create an adventure using inputs, outputs and variables to create a story!

Can you create a story like the one below - feel free to change the questions!

Variables 

• In programming, a variable is like a container that holds a piece of information. This information can be anything, like a number, a word, or even a whole sentence!

• For example, imagine you have a box that can hold a piece of fruit. You can put an apple in the box, and then later on, you can take the apple out and look at it. In programming, a variable is like that box. You can put information into the variable, and then you can use that information later on in your program.

Task 3 - Variables

We are now going to create a variable and then save some data to it. We will then output "print" this data to the screen.

Press the green play button to execute the code.

What type of information can be stored in a variable?

1. Only videos
2. Only sounds
3. Only pictures
4. Numbers, text, and other types of data

Selection Statements

Selection allows us to make decisions in our programs.  The code we use, are IF statements.

eg. IF I want to play on my PS5 THEN

I need to switch the PS5 on

Else I leave the PS5 switched off.

What does a selection statement do?

if, else - Example Program 

if, else - Program Flowchart

if, else, elif - Example Program

if, elif, else Statements

if, elif, else Statements 

Click here 

Indentation

• You may notice in my code, that some of the lines have been indented.
• There is a reason for this.
• Python requires indentation for the syntax.
• Indentation signifies the start and end of a block of code.
• Programs will not run.

Comparison Operators

Challenge Time!

Scenario

Age must be 18 to go into a club.

I want to go to a club, but I want to check whether I am old enough. If I am old enough, the program must say "You can go to the party" and if I am not old enough, the program must say, "You can't go to the party".

Comparison Operator you must use is -  >=

Debugging Task

Can you find out what is wrong with the code?

Click here

Answer

What is the comparison operator for not equal to?

1. !=
2. <=
3. >=
4. ==

What is a loop?

1. A set of instructions to complete a task.
2. A set of instructions in order.
3. A repeated section of code.
4. The end result of your program.

Why do we use loops in your programs?

1. To make the program run faster.
2. To make the program more efficient.
3. They allow decisions to be made.
4. They put information onto the screen,

What is a conditional statement?

1. A decision in a program.
2. A section of the program that loops.
3. A set of instructions in order.
4. An error in the code.

What is Syntax?

• The way we write a line of code is important, as the computer needs to recognise it.

• Think about our 'English'. It is important that we use correct punctuation, such as Commas and Full Stops. If we didn't, it would make our writing difficult to read.

• If we do not use the correct symbols and spellings in our Python coding, then the computer will not be-able to run our programs.

Task 2 - Debugging

In this task, you will need to debug the code using the error messages that create with code provide.

Click here

What is debugging?

• Debugging code refers to the process of identifying and fixing errors, bugs, or defects in a computer program that we have created.
  

• An error occurs, when you have done something wrong in your program. You could have spelt something wrong or even missed out a symbol...

Debugging Continued...

Create with code, shows you where your error is. Below is a screenshot that shows this.

What is debugging?

• Debugging code refers to the process of identifying and fixing errors, bugs, or defects in a computer program that we have created.
  

• An error occurs, when you have done something wrong in your program. You could have spelt something wrong or even missed out a symbol...

Task 2 - Debugging

In this task, you will need to debug the code using the error messages that create with code provide.

Click here

Debugging Continued...

Create with code, shows you where your error is. Below is a screenshot that shows this.

What is the process of checking a program for errors?

1. Error checking
2. De-bugging
3. Error finding
4. Mistake finding

Commenting our code. What is the importance?

• By commenting our code,  it tells you (the programmer) and anyone else who looks at the code what it does.

• By using the '#' symbol, it will not display when your code has been run.

Below is an example

What is the process of checking a program for errors?

1. Error checking
2. De-bugging
3. Error finding
4. Mistake finding

What type of information can be stored in a variable?

1. Only videos
2. Only sounds
3. Only pictures
4. Numbers, text, and other types of data

Recap: Operators

The below are essential when programming...

Let's take a look at the actual program...

Click here to take a look at how the program works

Let's look at why the program doesn't work properly!

Click here

'Make the students aware of data type casting'. This example is altered to show them!

How if, elif and else statements can be used

Click here

Can you...

Can you create your own program that uses if, elif and else?

I want you to create a program where:

If - you enter your name it prints("That is an awesome name")

elif - you enter John it prints("That is a good name")

elif - you enter Harry it prints("That is an ok name")

else - it prints("That isn't a good name")

What is Syntax?

• The way we write a line of code is important, as the computer needs to recognise it.

• If we do not use the correct symbols and spellings in our Python coding, then the computer will not be-able to run our programs.

What are conditional statements used for?

1. Breaking the code
2. Printing out all possible options
3. Making decisions based on certain conditions
4. Making the code run faster

Algorithm Efficiency

Efficiency is crucial in computer science. It involves measuring the performance and resource usage of algorithms. We will explore different measures and methods to assess efficiency.

Measuring Efficiency

Efficiency can be measured using time complexity and space complexity. Time complexity examines the time taken by an algorithm, while space complexity evaluates the amount of memory used.

 Big O Notation

Big O Notation describes the upper limit of the time complexity of an algorithm, indicating how the runtime of the algorithm grows as the size of the input data increases.

  

Why do we use Big O Notation

Used to analyse the efficiency of a search algorithm, such as demonstrating that binary search has a time complexity of O(log n).

CORRECT

CAUSE AN ERROR

print = ("Hello")

Print("Yes!")

print("this one)

name = imput("what is your name")

name = input("what is your name")

print("this text")

fav colour = "Green"

age = 10

print("Hello", name)

print("Bye",name")

Commenting our code. What is the importance?

• By commenting our code,  it tells you (the programmer) and anyone else who looks at the code what it does.

• By using the '#' symbol, it will not display when your code has been run.

Below is an example