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# Reasons why you should learn how to program with C++
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## Why?
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The first thing when you think of becoming a programmer is **HOW DO I START?** Well, **C++** is one of the best
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programming languages to give you insights into how a computer works. Through the process of learning how to code
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C++, you will learn not only how to use this language as a tool to solve your problems, but the farther you go, the
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more you will start uncovering and **exploring exciting computer concepts**.
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C++ gives you the **simplicity of C and adds a lot of steroids**. It delivers lots of quality-of-life stuff, increasing
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the developer experience. Let’s compare C with C++, shall we?
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1. The iconic book _"The C Programming Language" by Brian W. Kernighan and Dennis M. Ritchie_ has **only 263 pages**.
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Pretty simple, huh?
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2. The book _"C++ How to Program" by Harvey and Paul Deitel_ It holds around **1000 pages**, and the pages are way
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bigger than the other one.
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[![](https://media.tenor.com/VmsncHRDMlIAAAAC/spit-out-cereal-meme.gif)](https://tenor.com/view/spit-out-cereal-meme-wtf-wth-what-the-hell-gif-20467304)
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So, don’t worry, you just need to learn the basics first, and all the rest are somehow advanced concepts. I will do
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my best to keep you focused on what is relevant to each moment of your learning journey.
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Without further ado. Get in the car!
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[![](https://media.tenor.com/J55Pa8CbPH4AAAAd/dog-jump-car-jump.gif)](https://tenor.com/view/dog-jump-car-jump-cute-gif-15392159)
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## Speed Matters
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**A LOT**. Period. **C++** is one of the **closest intelligible programming languages before reaching the level of
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machine code**, as known as **Assembly Language**. If you code in machine code, you obviously will code precisely what
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you want the machine to do, but this task is too painful to be the _de-facto_ standard of coding. So we need
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something more straightforward and more human-readable. So C++ lies in this exact area of being close to assembly
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language and still able to be "easily" understandable. Note the quotes, they are there because it might not be that easy
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when you compare its syntax to other languages, **C++ has to obey some constraints to keep the generated binary fast**
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as a mad horse while trying to be easier than assembly. Remember, it can always get worse.
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[![](https://media.tenor.com/lc0byR9CdzAAAAAC/trampling-charge.gif)](https://tenor.com/view/trampling-charge-gif-19264241)
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## Why does speed matter?
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Mainly because we don’t want to waste time. Right? But it has more impactful consequences. Let’s think a bit more, you
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probably have a smartphone, and it lives only while it has enough energy on its battery. So, **if you are a lazy
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mobile developer and do not want to learn how to do code efficiently, you will make your app drain more energy
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from the battery** just by making the user wait for the task to be finished or by doing lots of unnecessary
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calculations! You will be the reason the user has not enough power to use their phones up to the end of the day.
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In fact, **you will be punishing your user by using your app**. You don’t want that, right? So let’s learn how to code
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appropriately. For the sake of the argument, worse than that, a lazy blockchain smart contract developer will make
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their users pay more for extra gas fee usage for the extra inefficient CPU cycles.
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[![](https://j.gifs.com/oY7PEL.gif)](https://gifs.com/gif/funcionrio-pblico-oY7PEL)
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## Language benchmarks
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I don’t want to point fingers at languages, but, hey, excuse me, python, are you listening to me, python? Python?
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Please answer!
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[reference cpp vs python](https://benchmarksgame-team.pages.debian.net/benchmarksgame/fastest/gpp-python3.html).
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Nevermind. It is still trying to figure things out. Ah! Hey ruby, don’t be shy, I know you look gorgeous, and I
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admire you a lot, but can you dress up faster and be ready to run anytime soon?
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You don’t need makeup to run fast. That’s the idea. If the language does lots of fancy stuff, it won’t be extracting the
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juicy power of the CPU.
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So let’s first clarify some concepts for a fair comparison. Some languages do not generate binaries that run in your
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CPU. Some of them run on top of a virtual machine. **The Virtual Machine(VM) is a piece of software that, in runtime,
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translates the bytecode or even compiles source code to something the CPU can understand.** It’s like an old car;
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some of them will make you wait for the ignition or even get warm enough to run fast. I am looking at you Java and
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JavaScript. It is a funny concept, I admit, but you can see here that the ones that run on top of a translation device
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would never run as fast as a compiled binary ready to run on the CPU.
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So let’s bring some ideas from my own experience, and I invite you to test by yourself. Just search for ["_programming
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languages benchmark_" on your preferred search engine](https://letmegooglethat.com/?q=programming+languages+benchmark).
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[![](https://media.tenor.com/AOfJ0ipRJkQAAAAC/tf2-pyro.gif)](https://tenor.com/view/tf2-pyro-teamfortress2-teamfortress2pyro-fire-gif-13656490)
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I don’t want to start a flamewar. Those numbers might be wrong, but the overall idea is correct. Assuming C++ does not
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add much overhead to your native binary, let’s set the speed to run as 1x. Java would be around 1.4x slower, and
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JavaScript is 1.6x, python 40x, and ruby 100x. The only good competitor in the house is Rust because its compiled code
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runs straight on the CPU efficiently with lots of quality-of-life additions.
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[Rust gives almost similar results](https://benchmarksgame-team.pages.debian.net/benchmarksgame/fastest/gpp-rust.html) if
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you do not play around with memory-intensive problems.
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[![](https://pics.me.me/me-i-need-64-bytes-of-memory-rust-yeah-umm-41882293.png)](https://me.me/i/me-i-need-64-bytes-of-memory-rust-yeah-umm-0d048f5778154bf3aa0bcd6dc1499677)
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## Who should learn C++
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[![](https://media.tenor.com/ur0xcQWCkegAAAAC/the-office-michael-scott.gif)](https://tenor.com/view/the-office-michael-scott-steve-carell-pointing-you-gif-15115246)
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**YOU!** Yes, seriously, I don’t know you, but I am pretty sure **you should know how to code in any language**. C++
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can be challenging, it is a fact, but if you dare to challenge yourself to learn it, your life will be somewhat better.
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Let’s cut to the bullets:
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1. The ones who seek to build efficient modules for mobile apps, such as the video/image processing unit;
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2. Game developers. Even the gameplay developers that usually only script things should know how to ride a horse(CPU)
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fast;
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3. Researchers looking to not waste time by coding inefficient code and wait hours, even days, to see the result of
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their calculations. They should reduce the costs of renting CPU clusters;
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4. Computer scientists are those who should know how a computer works. After all, C++ is one of the preferred
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programming languages that unlocks all the power of the CPU;
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5. Engineers, in general, should know how to simulate things efficiently;
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## How do machines run code?
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The first thing is: the CPU does not understand any programming language, only binary instructions. So you have to
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convert your code into something the machine can understand. This is the job of the compiler. **A compiler is a
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piece of software that reads a text file written following the rules of a programming language and essentially
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converts it into binary instructions that the CPU can execute**. There are many strategies and many ways of doing it.
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So, given its nature of being near assembly, **with C++, you will control precisely what instructions the CPU will
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run**.
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But, there is a catch here: for each CPU, you will need a compiler for that instruction set. Ex.: the compiler GCC can
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generate an executable program for ARM processors, and the generated program won’t work on x86 processors; In the same
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way, an x64 executable won’t work on an x86; you need to match the binary instructions generated by the compiler with
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the same instruction set available on the target CPU you want to run it. Some compilers can cross-compile: the compiler
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runs in your machine on your CPU with its instruction set, but the binary generated only runs on a target machine with
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its own instruction set.
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[![](https://www.tutorialspoint.com/compiler_design/images/language_processing_system.jpg)](https://www.tutorialspoint.com/compiler_design/compiler_design_overview.htm)
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# Program Life Cycle
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Software development is complex and there is lots of styles, philosophies and standard, but the overall structure
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looks like this:
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1. Analysis, Specification, Problem definition
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2. Design of the Software (pseudocode/algorithm, flowchart), Problem analysis
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3. Implementation / Coding
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4. Testing and Debugging - In TDD(Test Driven Development) we write the tests first.
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5. Maintenance - Analytics and Improvements
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6. End of Life
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# Pseudocode
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> Pseudocode is a way of expressing algorithms using a combination of natural language and programming constructs. It
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is not a programming language and cannot be compiled or executed, but it provides a clear and concise way to
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describe the steps of an algorithm. Here is an example of pseudocode that describes the process of finding the
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maximum value in a list of numbers:
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> ```
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> set maxValue to 0
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> for each number in the list of numbers
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> if number is greater than maxValue
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> set maxValue to number
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> output maxValue
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> ```
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> Pseudocode is often used as a planning tool for programmers and can help to clarify the logic of a program before it
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is written in a specific programming language. It can also be used to communicate algorithms to people who are not
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familiar with a particular programming language. [Reference](https://chat.openai.com/)
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# Flowcharts
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> A flowchart is a graphical representation of a process or system that shows the steps or events in a sequential
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> order. It is a useful tool for demonstrating how a process works, identifying potential bottlenecks or
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> inefficiencies in a process, and for communicating the steps involved in a process to others.
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>
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> Flowcharts are typically composed of a series of boxes or shapes, connected by arrows, that represent the steps in
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> a process. Each box or shape usually contains a brief description of the step or event it represents. The arrows
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> show the flow or movement from one step to the next.
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>
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> Flowcharts can be used in a variety of settings, including business, engineering, and software development. They
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> are particularly useful for demonstrating how a process works, identifying potential issues or bottlenecks in the
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> process, and for communicating the steps involved in a process to others.
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>
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> There are many symbols and notations that can be used to create flowcharts, and different organizations
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> and industries may have their own standards or conventions for using these symbols. Some common symbols and
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> notations used in flowcharts include:
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>
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> 1. Start and end symbols: These are used to indicate the beginning and end of a process.
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> 2. Process symbols: These are used to represent the various steps or events in a process.
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> 3. Decision symbols: These are used to represent a decision point in a process, where the flow of the process depends on the outcome of a decision.
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> 4. Connector symbols: These are used to connect the various symbols in a flowchart, showing the flow or movement from one step to the next.
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> 5. Annotation symbols: These are used to add additional information or notes to a flowchart.
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>
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> By using a combination of these symbols and notations, you can create a clear and concise flowchart that effectively communicates the steps involved in a process or system. [Reference](https://chat.openai.com/)
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I suggest using the tool [Code2Flow](https://code2flow.com/) to write pseudocode and see the flowchart drawn in real
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time. But you can draw them on [Diagrams](https://diagrams.net).
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# Practice
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Try to think ahead the problem definition by questioning yourself before expressing the algorithm as pseudocode or
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flowchart:
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- What are the inputs?
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- What is a valid input?
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- How to compute the math?
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- What is the output?
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- How many decimals is needed to express the result?
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Use [diagrams](https://diagrams.net) to draw a flowchart or use [Code2Flow](https://code2flow.com/) to
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write a working pseudocode to:
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1. Compute the weighted average of two numbers. The first number has weight of 1 and the
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second has weight of 3;
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2. Area of a circle;
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3. Compute GPA;
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4. Factorial number;
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# Glossary
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- CPU
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- GPU
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- ALU
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- Main Memory
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- Secondary Memory
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- Programming Language
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- Compiler
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- Linker
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- Assembler
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- Pseudocode
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- Algorithm
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- Flowchart
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# Activities
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1. Sign up on [beecrowd](https://www.beecrowd.com.br). If you are a enrolled student, look for the key in canvas
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to be assigned to the coding assignments.
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2. https://blockly.games/mazeLinks - test your ability to solve small problems via block programming
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3. https://codecombat.com/ - very interesting game
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# Troubleshooting
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If you have problems here, start a
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[discussion](https://github.com/InfiniBrains/Introduction-to-Game-Programming-With-CPP/discussions) this is publicly
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visible and not FERPA compliant. Use discussions in Canvas if you are enrolled in a class with me.

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