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numbers_and_arithmetic.step

goals do
  goal "Understand the difference between an integer and a float"
  goal "Perform basic arithmetic operations"
end

step do
  message "In programming, we like to distinguish between different kinds of
    numbers. Here, we'll talk about integers (whole numbers) and floats
    (decimals)."
  irb <<-TRYME
1.class
1.0.class
TRYME
  message "You'll notice that `1.class` and `1.0.class` are actually 2 different
    kinds of objects."
  message "With that in mind, let's see how that plays into performing
    arithmetic operations."
end

step do
  irb <<-TRYME
1 + 2
1.0 + 2.0
1 + 2.0
TRYME
  message "Here, you'll notice that performing an operation on 2 integers will
    produce an integer and operating on 2 floats will produce a float, but mixing
    an integer with a float would actually produce a float."
end

step do
  irb <<-TRYME

2 - 1
2.0 - 1.0
2.0 - 1
TRYME
  message "Just like addition, we can perform subtraction on integers and floats interchangeably."
end

step do
  irb <<-TRYME

2 * 3
2.0 * 3
2.0 * 3.0
TRYME
  message "Likewise, we can perform multiplication on floats and integers."
end

step do
  irb <<-TRYME

4 / 2
8 / 2
6 / 4
6 / 4.0
TRYME
  message "Division can be performed similarly. Notice the difference in the results of the last two lines. When dividing two integers, ruby will perform mathematical truncation, where the expected result 1.5 becomes 1"
end

step do
  irb <<-TRYME

4 / 0
TRYME
  message "Uh oh! Notice how we did not get a result here. The ruby interpreter raised an error. These errors tell the programmer that they tried to do something that the interpreter does not like or cannot use. Each error has a classification and a message. In this case, we get a `ZeroDivisionError` with the message: divided by 0"
end

challenge do
  message "Write a calculator that performs addition. Your program should prompt the user to enter two numbers and output the sum."

  message 'Here is a sample of how the program might run. The `>` has been used below to indicate that the user should input the value proceeding it.'

  source_code <<-'CONTENTS'
What is the first number?
> 2
What is the second number?
> 4
The sum is 6
CONTENTS

end

next_step "booleans"