Before completing this quiz, we invite you to revisit the main Big O Notations used to describe the time complexity and space complexity of an algorithm..
The main Big O Notations this quiz will focus on are:
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Reserved Keywords of the Python Language
If you have reached this page, you have probably already started to learn to code using a high-level programming language such as Python, JavaScript, C, php or Ruby. But what does “learning a new programming language” involve?
Learning a programming language is, to some extent, like learning a foreign language. It will require you to learn the words this language is made of. The good news is, unlike modern languages such as English, Arabic, French or Mandarin, programming languages have a very limited number of words for you to learn: these are the reserved keywords and built-in functions of the language.
Let’s compare different programming and non-programming languages!
English?
🗩
According to the Oxford English Dictionary, the English language contains more than 170,000 words!
Python?
💻
Python v3.6 contains exactly 33 reserved keywords and 71 built-in functions.
Hindi?
🗩
It is estimated that the Hindi language contains between 150,000 and 185,000 words.
HTML?
💻
The HTML (version 5.2) language contains 142 different tags.
CSS?
💻
The CSS (version 3.0) language contains around 520 distinct properties.
French?
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According to the Larousse dictionary, the French language has approximately 135,000 words.
Java?
💻
Java contains exactly 53 reserved keywords with an additional 4,000 built-in functions in the JDK.
It is believed that to be able to be able to take part in every day conversations in a foreign language, you need to know around 2,000 to 3,000 words. To be fluent in a language, you would need to know between 5,000 to 10,000 words!
Luckily, to become a proficient programmer using a programming language, you do not need to remember that many words!
As you have started to learn Python, you can test yourself to see how many of the reserved keywords and built-in functions you can remember by completing the quiz below!
Python QuizOpen in New Window
101 Binary Watch
A binary watch uses 18 LEDs to give the HH:MM:SS time using three binary numbers each consisting of 6 bits.
The following diagram can help you understand how to work out the time displayed on a binary watch:
Using the above diagram we can work out the actual time being displayed:
Your Task:
Can you tell what is the time displayed by each of the following binary watches:
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HH:MM:SS: (view solution) |
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HH:MM:SS: (view solution) |
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HH:MM:SS: (view solution) |
The FDE Cycle… In your own words
Before completing this task, you will need to revisit the main characteristics of the Von Neumann Processor Architecture.
You task is to write a description in your books or on the space provided below to describe, in your own words, how the FDE cycle works. Your description needs to include as many of the following key terms as possible.
| Fetch | Instruction | Register |
| Decode | Data | Program Counter |
| Execute | Memory location | MAR |
| Primary Memory | Control Unit | MDR |
| RAM | ALU | Accumulator |
| Binary | Clock speed | GHz |
The FDE Cycle… in your own words!
Describe, in your own words, how the FDE cycle works within the CPU. Use as many of the keywords provided above as possible.
Word Count: 0
Solution...
The solution for this challenge is available to full members!Find out how to become a member:
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Anatomy of a computer program
Computer programs are a set of step-by-step instructions used to teach the computer how to complete a task.
Computer programs are written using a specific programming language. Nowadays, most programmers would write code using a high-level programming language such as Python, C, C#, Java, Ruby or Basic.
If we were to dissect a computer program, we would find the following elements:
- Reserved Keywords & Built-in Functions
- Identifiers (e.g. for variables and subroutines)
- Values of different data types
- Computing Operators
- Punctuation signs
- Comments/Annotations
Let’s investigate these elements further… Click on the sub sections below to find out more.
Punctuation signs
Each language has its own syntax and its own set of punctuation signs. In the English language the example of punctuation signs are the comma ,, the full stop., the question mark ?. And syntax in a language do matter as omitting or using the wrong punctuation sign it can alter the meaning of a message. For instance, would you go swimming in these waters, knowing that “crocodiles do not swim here”?
Programming languages have their own syntax too. Not using the correct syntax in your code will generate a syntax error. This means that your computer cannot interpret your code and hence will not run it.
In Python, the main punctuation signs are the brackets (, ), [, ], { and } the colon : and the comma ,.
Programming languages have their own syntax too. Not using the correct syntax in your code will generate a syntax error. This means that your computer cannot interpret your code and hence will not run it.
In Python, the main punctuation signs are the brackets (, ), [, ], { and } the colon : and the comma ,.
Your Task
Your task is to identify all the different elements of the short program below, and drag them in the corresponding sections.
Anatomy of a Computer Program – Drag and DropOpen in New Window
The Von Neumann Processor Architecture
John Von Neumann (1903-1957) was a Hungarian-American mathematician, physicist and computer scientist and a founding figure in computer science, with significant contributions to computing hardware design.
The Von Neumann architecture refers to a processor architecture which has access to a program stored in primary memory as a set of instructions. A processor based on the Von Neumann architecture can execute these instructions sequentially using the Fetch Decode and Execute cycle (FDE Cycle).
Nowadays most general purpose computers are still relying on the key characteristics of this architecture. Within the Von Neumann architecture the processor consists of a control unit, an arithmetic logic unit (ALU) and some key registers used to store numerical values within the processor. These include a Program Counter (PC), an Accumulator, a Current Instruction Register (CIR), a Memory Data Register (MDR) and a Memory Address Register (MAR). These registers are used during the FDE cycle for the processor to fetch instructions and transfer data (between the processor and primary memory) and to execute these instructions.
The rate at which a processor can perform the FDE cycles to process instructions is called the clock speed. For instance, a processing unit with a 3.5GHz clock speed can process 3,500,000,000 instructions per second.
Recent computers have a high clock speed and more advanced processors may also have multiple cores (dual core, quad core etc.) which enable them to process several FDE cycles simultaneously. They may also contain cache within the CPU which can be used to store (and retrieve at a very fast rate) recently or frequently used instructions or data without the need to retrieve these from primary memory. A Central Processing Unit (CPU) with multiple cores, a certain amount of cache and a high clock speed will lead to an increase of the performance of the CPU.
Inside the CPU – Drag and DropOpen in New Window
Poem Decoding Challenge
To celebrate the start of the Winter, we have asked our Artificial Intelligence “AI-101” to generate a poem about the cold winter weather. The AI has generated the following poem which consists of a list of numbers! We believe the poem is in a compressed format. We found within the log of the AI a hash table (codebook) as appearing on the tablet below.
We believe this codebook is the key to uncompress the poem. (Click on the picture below to open full screen)
Challenge #1
Use the above codebook and printed poem to reveal the title and 8 verses of this poem.
Challenge #2
Implement a recursive algorithm to uncompress this poem using the given hash table by completing the code below.
Solution...
The solution for this challenge is available to full members!Find out how to become a member:
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Tagged with: recursion
Playing Cards Sorting Algorithm
The aim of this online activity is to sort a set of 8 playing cards randomly picked from a deck of cards based on the following rules:
- The cards need to be sorted in ascending order of their values. For the purpose of this task, an Ace will be the lowest value (1) whereas a King will be the highest value (13).
- In order reveal a card you need to click on it to flip it. However you will only be able to reveal two cards at a time.
- Should you decide to swap two cards, you will need to drag one of the card on top of the other card. Both cards will then swap position.
- If you believe a card is in position, you can tick the checkbox underneath it.
- If you believe all 8 cards are sorted, you can click on the “Check if cards are sorted” button. If they are in the correct order, from lowest to largest value, all 8 cards will be revealed.
- At anytime, you can start this task again with a fresh set of cards by clicking the “New Cards” button.
Your aim is to find a method (algorithm) that works for you and enable you to sort all the cards with a minimum number of swaps.
Playing Cards Sorting ChallengeOpen in New WindowSorting Algorithms
They are a range of different algorithms that can be used for a computer to sort a list of values. You can investigate some of the most widely used sorting algorithms using the following blog posts:
Logic Gates Circuits used in a Theme Park
In this set of challenges, you will design and test some logic gates circuits to control different automated systems used to control the following rides of a Theme park:
- Ferris Wheel
- Drop Tower
- Roller Coaster
Ferris WheelDrop TowerRoller Coaster
Ferris Wheel
A Ferris Wheel automated control system controls whether the wheel should be spinning or should be stopped.
The automated system is based on the following inputs:
- A main switch is controlled by the main operator to decide if the wheel is in operating (spinning) or not.
- If the switch is on, the wheel is spinning
- If the switch is off, the wheel is not spinning, allowing for passengers to load/unload a cabin.
- Weight sensors are also used in each of the cabins of this Ferris wheel. A sensor is “on” if the cabin it’s on is overloaded (too heavy). If any of the sensors is on, the wheel is automatically stopped. For the purpose of this task, we will assume that our Ferris Wheel only contains 4 cabins. We will therefore only use 4 sensors. In reality, more sensors would be needed.
Use our logic gates circuit simulator to design and test a circuit for the Ferris Wheel automated control system. (Click on picture below)
Drop Tower
To join the queue to get on board the Drop Tower, the passengers must comply with some safety rules. A control panel is available to control a gate to let a passenger join the queue. The control panel has 3 switches as follows:
- Switch A to indicate whether the passenger is 12 or over.
- Switch B to indicate whether the passenger is at least 4-feet tall.
- Switch C to indicate whether the passenger is accompanied by an adult.
For the gate to open to let the passenger join the queue for the ride, the rules are as follow:
- The passenger must be at least 4-feet tall.
- The passenger must either be 12 or over and if not, they must be accompanied by an adult.
Click on the picture below to design and test the logic gates circuit to control the gate, so that if a passenger is allowed to get on board the Drop Tower, the gate is “on”, but if not the gate is “off“.
Roller Coaster
An emergency stopping system controls whether a signal should be sent to the train of a roller coaster to stop it, in case of an emergency. The system is based on the following inputs:
- A main switch is controlled by the main operator to start (switch is “on”) or stop (“off”) the roller coaster. There are however only three locations on the track where it is safe for the roller coaster to be stopped.
- There are 3 sensors on the track, one on each of these 3 locations. The sensor is “on” if it detects the train at this given location. At least one of the three sensors must be on for the train to be stopped.
- A safety guard sensor is also used to detect if any of the safety guards are not securely locked in. When all safety guards are locked in, the sensor is “on”.
If any of the safety guards are unlocked, the sensor is “off”: In this case, the train should automatically be stopped provided that the train is at one of the three safe locations to be stopped.
Use our logic gates circuit simulator to design and test a circuit for the Roller Coaster Emergency Stopping System.
Solution...
The solution for this challenge is available to full members!Find out how to become a member:
➤ Members' Area
Tagged with: logic gates
Code Maintainability Q&A
Question 1[4 marks]
The two Python scripts above were created by an IT manager of a school and are performing exactly the same task: to generate a username based on the student’s firstname, lastname and year group. Compare both of these scripts and identify what was done to the code to make it easier to understand, maintain and re-use in future projects?
Question 2[2 marks]
The IT manager would like to make this program more robust by adding a validation check on the year group. The school only has students in year 7 to year 13. How could the IT manager change the code above to make sure the user can only enter a value between 7 and 13 for the year group?
Question 3[4 marks]
The IT manager would like to test his new validation check on the year group. Identify 4 pieces of test data that the IT manager should use to perform a normal/valid test, an invalid test, a boundary test and an erroneous test?
Normal/Valid Test Data:
Invalid Test Data:
Boundary Test Data:
Erroneous Test Data:
Invalid Test Data:
Boundary Test Data:
Erroneous Test Data:
LMC Simulator
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