jritten/nyiema_bayfield

Solo Warm-up Challenge

Directions

Read carefully. By now, you understand that reading technical documents is hard. It's also a skill required of software engineers, and you can practice this during this challenge. We've made these instructions as clear as we know how, and need you to demonstrate your attention to detail and commitment to quality by meeting the requirements below. If something is confusing, ask.

• You should do this challenge solo.
• You should clone this repo and make a branch for your work. Commit Often!.
• You should write your code in the file runner.rb.
• Anything that isn't Ruby code should be in comments.
• You may use Google, books, and other resources for help, but do your own work.
• Do not copy and paste code that you do not understand.
• When you're finished, do a final commit and push your branch to github.
• Write tests, like this: p my_method(input) == 'expected outcome'. This puts a happy true to the console when the method is returning the expected outcome. We have given you examples! Use those examples and expand on them -- write more that include the edge cases you can think of. Write tests before you write code and execute the tests continuously while coding.
• Include all driver code and tests in your submission. Your runner.rb file will ideally be error-free Ruby that puts lots of true when run.
• If you run into issues completing this work, ask any instructor for help.

Exercise 1

Define two local variables: first_name and last_name, and assign them the values of your own names.

Exercise 2

Use #each to write a method called calculate_product which takes as its input an array of integers and returns their product. For example

puts calculate_product([1,2,3]) == 6 # this test puts 'true' if calculate_product([1,2,3]) returns the correct value of 6
puts calculate_product([0,-1,-10]) == 0 
puts calculate_product([1,-1,-10]) == 10 
puts calculate_product([]) == nil

Your solution should use each, not an enumerable method. If you would prefer to write this with an enumerable, note which method(s) you'd use in a comment.

Exercise 3

Explain in plain English what each of these methods does and the value each returns. Ensure your answer is written as a comment. You may want to look up the syntax for multi-line comments.

def format_name(name)
  return "#{name[:last]}, #{name[:first]}"
end

def display_name(name)
  puts format_name(name)
end

Exercise 4

Write a method find_missing_number that returns the number missing in a list of sequential numbers from 1 to 10,000. Your method's input will be a comma-separated string (e.g., "1, 2, 3, etc."). There will only be one missing number.

string_missing_7    = (1..10000).reject { |x| x == 7 }.join(",")
string_missing_4567 = (1..10000).reject { |x| x == 4567 }.join(",")
string_missing_9999 = (1..10000).reject { |x| x == 9999 }.join(",")


puts find_missing_number(string_missing_7) == 7         
puts find_missing_number(string_missing_4567) == 4567
puts find_missing_number(string_missing_9999) == 9999

What are the most difficult missing numbers to detect? Write tests for those.

Exercise 5

Define a House class, and model the behavior of a house. Each house should have its own state, meaning that I can create many different instances of the House class, each with its own unique property values.

• Each house has its own current_temp (e.g. 67).
• Each house has its own minimum_temp and maximum_temp (e.g., 62 and 70, respectively). Your client wants exactly these variable names.
• Each house has its own heater_on and ac_on status (true if on, false if off).
• The heater_on and ac_on properties are set to false when a house is instantiated.
• The House initialize method accepts three arguments: a current temp, a minimum temp, and a maximum temp.
• The House initialize method throws an ArgumentError if more or less than three arguments are passed.
• Calling toggle_heater on an instance of House turns the heater on/off.
• Calling toggle_ac turns the air conditioner on/off.
• Only the heater or the air conditioner will be on at any given time, never both.
• Calling update_temp! increases or decreases the current temperature depending on if the heater or the air conditioner is on.
• When the heater is on, update_temp! increases the current_temp by 1 unit.
• When the air conditioner is on, update_temp! decreases the current_temp by 2 units.
• When the current_temp rises above the maximum_temp, the air conditioner turns on and the heater should be off.
• When the current_temp falls below the minimum_temp, the heater turns on and the air conditioner should be off.

You will need to write driver code like this -- my_house = House.new(75, 60, 80) -- before you can test your code.