COMP-200: Intro to Computer Systems

Assignment 1

mo khan - 3431709

Choose ONE exercise each from Chapters 2 and 3

Chapter 2:

Write an algorithm that gets the price for item A plus the quantity purchased. The algorithm prints the total cost, including 6% sales tax.

Pseudocode

Get values for `price` and `quantity`
Set the value of `tax` to 1.06
Set the value of `total` to `price` multiplied by `quantity` multiplied by `tax`
Print the value of `total`

Ruby code

def calculate_total(price, quantity, tax = 0.06)
  (price * quantity) * (1.0 + tax)
end

Chapter 3:

Use the binary search algorithm to decide whether 35 is in the following list: 3, 6, 7, 9, 12, 14, 18, 21, 22, 31, 43

Pseudocode

Get the list of numbers and assign to variable `items`
Get the target number and assign to variable `target`
Set variable `min` to 0
Set variable `max` to total # of `items`
Set variable `mid` to `max - min / 2`
Set variable `found` to No
while (mid > min && mid < max)
  Set the variable `current` to `items` at index `mid`
  if current = target
    Set variable `found` to Yes
    Set variable `mid` to `min - 1`
  else if target > current
    Set variable `min` to the value of `mid`
    Set the variable `mid` to `((max-min) / 2) + min`
  else
    Set variable `max` to the value of `mid`
    Set the variable `mid` to `((max-min) / 2) + min`
  end
end of loop
If Found = Yes
  print Found
else
  print Not Found
stop

Ruby code

def bsearch(target, items)
  min = 0
  max = items.size
  mid = (max - min) / 2

  while (mid > min && mid < max) do
    current = items[mid]

    if target == current
      return true
    elsif target > current
      min = mid
    else
      max = mid
    end

    mid = ((max - min) / 2) + min
  end

  return false
end

What numbers will be compared with 35?

00	01	02	03	04	05	06	07	08	09	10
03	06	07	09	12	14	18	21	22	31	43

00	01	02	03	04
18	21	22	31	43

00	01
31	43

00
43