Week 13 HW - What's inside

Synopsis You have 2 deliverables:

1. A Github Repo with 2 seperate express apps with simple yet tricky functionality
2. An exercise that requires you watch/complete a module from MYGA and then answer some questions about some code that is provided.

Practical Homework: First Express Homework(build 2 express apps in the same git repo)

Practice the Basics of Express

Learning Objectives

• Set up some express servers for practice
• make some get routes
• use url/query parameters

Prerequisites

• Nodejs
• npm packages
• Introduction to expressjs
• Request/response/ how the internet works basics
• Basic understanding of routing
• JavaScript, HTML fundamentals

Technical Requirements

1. Must be able run without syntax errors (ok if it breaks after the user tries to do something, though do try to comment on the code that isn't working)
2. Must get functionality required for each section working

Learning Objectives

• Practice setting up express applications.
• Practice creating custom routes.
• Practice using parameters from a request.

Getting Started

In the software_homework/unit_2/week-13 directory run git init, then create a file called hw-part-one Javascript file server.js. Write your answers inside this one js file for Greetings, Tip Calculator & Magic 8 Ball

• npm init -y. You should receive a package.json.

Install express. npm i express. Check your files.

:elephant: Hint: You can check to make sure your installation was successful in one of the following places:

• Your package.json file should have express listed in the dependencies.
• You could also check in your node_modules folder to see anexpress folder.
• Require express and set the app. (look back to the markdown from today if you need more help on how to do this).
• Tell the server where to listen for requests (the port).

Greetings

2. Make a route '/greeting' that sends a generic greeting to the screen like "Hello, stranger".
3. Give the greeting route a param /:name
4. When hitting the route, the page should display a message such as "Hello, ", or "What's up, <name>", or "<name>! It's so great to see you!" (ex. hitting '/greeting/Jimmy-boy' should display Wow! Hello there, Jimmy-boy on the page).

🔴 Commit

Tip Calculator

2. Your app should have a route of '/tip' and it should expect 2 params. One should be total and one should be tipPercentage.
3. When hitting the route, the page should display how much your tip will be based on the total amount of the bill and the tip percentage. (ex. hitting '/tip/100/20' should display 20 on the page).

🔴 Commit

Magic 8 Ball

2. Create a route of '/magic' that should expect a phrase in the URL that ask the Magic 8 ball a question.
3. So if the user hits that route and asks a question of "Will I be a Millionaire" (ex. '/magic/Will%20I%20Be%20A%20Millionaire') he should have return to him his question AND a random Magic 8 ball response (see the array below) on the screen.
4. We can't use spaces in the url, so we use %20 to express a space in the url.
5. So if the user hits that route and asks a question of "Will I be a Millionaire" he should get his question asked and a random Magic 8 ball quote on the screen.
6. Send the magic 8 ball response back between html <h1> tags
7. Use this array of Magic 8 ball responses.....

["It is certain", "It is decidedly so", "Without a doubt", "Yes definitely","You may rely on it", "As I see it yes", "Most likely", "Outlook good","Yes", "Signs point to yes", "Reply hazy try again", "Ask again later","Better not tell you now", "Cannot predict now", "Concentrate and ask again","Don't count on it", "My reply is no", "My sources say no","Outlook not so good", "Very doubtful"]

🔴 Commit

Take one Down and Pass it Around

In a folder parallel to hw-one You will now Build a second express application that enables users to count down the number of bottles of beer. Don't like beer? Pass around bottles of soda, kombucha, or milk etc.

Instructions

• cd .. (you are trying to go back to sowftare_homework/unit-2/week-13)
• mkdir pass-it-around
• cd pass-it-around
• npm init -y
• build a basic express server (this is the second part of the hw)
• You will now have 2 node js apps inside the same git repo.

Requirements

• On the home page (get "/"), users should see:

  • "99 Bottles of beer on the wall"
  • a link that says "take one down, pass it around"
  • this should link to /98, where the number represents the number of bottles left.

• When a number is given in the url (get "/:number_of_bottles"), users should see:

  • The number of bottles of beer on the wall (i.e. 98 Bottles of beer on the wall.)
  • a link to "take one down, pass it around", where the href is number of bottles in the parameter minus 1.

• If there are 0 bottles left, do not show a link to "take one down"

  • Add a link to start over, which directs the user back to the home page.

Hints

• You should use an anchor tag with an href to link to the next 'page'

Bonus

• Have some more fun

Update your page to be something like

99 little bugs in the code
99 little bugs
Take on down
Patch it around
127 bugs in the code

Make the bugs go down by one, but then have some sort of functionality where the bug count can randomly go up

You have a lot of freedom to make it work how you want!

Hungry for more?(bonus)

Fibonacci

Back in your main app:

1. Add Fibonnaci as a comment in your application.
2. Create a route 'fibonacci'
3. This route will take one param, the number we will operate on.
4. If the number param is not a fibonacci number, print out "I can tell this is not a fibonacci number."
5. If the number is a Fibonacci number print out "Very good. It is Fibonacci."

🔴 Commit

Deliverables:

• A GitHub repository containing your project code on github.com

Evaluation Criteria:

• Correctness and completeness of your code.

Happy coding!

Theoretical HW(Big O Notation)

Big O Notation

Overview

This lesson covers the basics of Big O notation.

There are two components to this lesson:

1. myGA module: Big O Notation
2. Delevirable Exercise: Analyzing Algorithms shown at the bottom

If the link doesn't work follow these instructions

1. Log into myGA Dashboard
2. Look for Introduction to Computer Science and open it
3. Go to the Big O Notation Lesson

Learning Objectives

By the end of this lesson, you'll be able to:

• Explain how Big O notation is used to describe algorithms.
• Define constant, linear, quadratic, logarithmic, and factorial Big O runtimes.
• Analyze algorithms to determine their Big O runtime.

Prerequisites

• None

Duration

1.5 hours total:

• 0.5 hour myGA
• 1 hour in exercise

Additional Resources

• The Big O Cheat Sheet is the authority on Big O complexities.

Big-O Notation Exercises

Instructions

1. Read each function below and analyze it
2. In a Codepen describe what the function does and then answer What is the worst-case time complexity for the algorithm aka the Big O?

#1

function wordOccurrence(word, phrase){
  let result = 0
  const array  = phrase.split(' ')
  for(let i = 0; i < array.length; i++){
    if(word.toLowerCase() === array[i].toLowerCase()){
      result++;
    }
  }
  return result
}

#2

function bubble_sort(list){
  for(let i = 0; i < list.length - 1; i++){
    for(let j  = 0; j < list.length - 2; j++){
      if(list[j+1] < list[j]){
        const temp = list[j];
        list[j] = list[j+1];
        list[j+1] = temp;
      }
    }
  }
  return list;
}

#3

function factorial(n){
  if(n === 0){
    return 1;
  }else{
    return n * factorial(n-1);
  }
}

#4

function bobIsFirst(people){
  return people[0] == 'bob'
}

#5

function isPalindrome(input){
  const stack = [];
  let output = "";
  for(let i = 0; i < input.length; i++){
    stack.push(input[i]);
  }
  while(stack.length){
    output += stack.pop();
  }
  return output == input
}

#6

function sumOfDivisors(n){
  let result = 0;
  let i = 1;
  while(i < n){
    if( n % i == 0){
      result += i;
    }
    i++;
  }
  return result
}

#7

function printAllNumbersThenSumPairs(numArray){
  numArray.forEach((num)=>{
    console.log(num);
  });
  numArray.forEach((num, index)=>{
    if(index < numArray.length - 1){
      console.log(num + numArray[index+1])
    }
  });
}

#8

function isPrime(num){
  if(num == 1 || num == 2){
    return false
  }
  for(let i = 2; i < num - 1; i++){
    if(num % i == 0){
      return false
    }
  }
  return true
}

Deliverables:

• A GitHub repository containing your project code on github.com

Evaluation Criteria:

• Correctness and completeness of your code.