CS 111X - Fall Test 1

Transcription

1 CS 111X - Fall Test 1 1/9 Computing ID: CS 111X - Fall Test 1 Name: Computing ID: On my honor as a student, I have neither given nor received unauthorized assistance on this exam. Signature: First, write your name and ID, pledge this test, and bubble your ID on this page. Failure to do so will result in penalty points. This is a closed note, closed book, closed computing device, 50-minute test. You are not to speak with anyone except the instructor or TA for any reason except an emergency during the test. Important: Students may take this test at different times. It is a violation of the Honor Code to talk about the test in any way with a student who has not yet taken it. All questions MUST be answered only on the page on which they are asked (answers on scratch paper or on other pages will not be accepted). Also, hard questions may be mixed with easy questions. If you start a question and it s hard or time-consuming, you might want to save it for the end of the test and go ahead and work on easier problems. State any additional assumptions you make. Good luck!

2 CS 111X - Fall Test 1 2/9 Computing ID: Question 1 Primitive Data Types / Casting [34 points] Give the resulting data type and value of each of the following Python expressions. The first one is done for you as an example. If the code would be an error, write error in both blanks. (1 pt. per blank) Expression type value a. 2-3 int -1 b // 8 c. 15 % 5 d. 4 + float( 5 ) e. int(87.999) f. 3 ** 3 g. str(2) + 9 h i. str(34) j k l. Which of the the following is a syntax error? Which is a runtime error? Which is a logical error? Write syntax, runtime, or logical in the blanks below. (9 pts.) Attempting to access an out-of-range list index. Forgetting a ) at the end of a statement where one is required. Adding sales tax value before applying a $5 discount. m. Given the following variables, circle the expression below that evaluates to false. (5 pts.) p = True q = False p or q p or not(q) p and q p and not(q) not(p and q)

3 CS 111X - Fall Test 1 3/9 Computing ID: Question 2 - Python Statements [20 points] a. Given a list called nums, write ONE line of code to add the first and last elements together and store the result in a variable called result. (5 pts.) b. Write an if statement that will print Yes! if a number called num is evenly divisible by 3. (5 pts.) c. Describe the circumstances in which you should use a while loop instead of a for loop. (5 pts.) d. Convert the following code to one if-elif-else statement with each of the three cases (5 pts.) x = 0 if x > 60 : if x >= 90 : print ( "A" ) if x < 90 and x > 70 : print ( "B" ) if x < 70 : print ( "C" ) else: print ( "D" )

4 CS 111X - Fall Test 1 4/9 Computing ID: Question 3 - Decision and Control Structures [15 points] a. What is the value of result after this code runs? Write your answer in the box. (5 pts.) x = 5 y = False result = "" if x >= 10 : if not y: result = "medium" else : result = "average" elif x <= 13 : if not y: result = "large" else : result = "big" else : result = "small" b. Convert the following while loop into a for loop that produces the same output. Write your answer in the box. (5 pts.) i = 7 while i > -3: print (i*i) i -= 1 c. What is the output of the following code. Write your answer in the box. (5 pts.) greeting = "Hello, World!" sub = greeting[ : 5] + greeting[7 : len(greeting)-1] print(sub)

5 CS 111X - Fall Test 1 5/9 Computing ID: Question 4 - Programming [30 points] An Online Store Assume you have the following dictionary, where the key is the book title and the value is the price (in US dollars): store = { book1 : 12, book2 : 14, book3 : 15, book4 : 8 } Write a program that simulates an online store ordering system. Your program should prompt the user to add a copy of a book to their order by typing the name of the book or typing quit to finish the order. The program should then print the final total of all items in the order. Note that the program should let the user know if they try to buy a book that doesn t exist in the list. INPUT: The names of books that should be added to the order or quit to print the total and end the program. OUTPUT: The final output is the total of the entire order. EXAMPLE: (match the wording shown here) Add to order (quit to quit): book1 Current total: $12 Add to order (quit to quit): book3 Current total: $27 Add to order (quit to quit): quit Your grand total is $27 Another run might look like this: Add to order (quit to quit): book7 We don't have that book! Add to order (quit to quit): book2 Current total: $14 Add to order (quit to quit): quit Your grand total is $14 Put your answer on the next page. Nothing on this page will be graded.

6 CS 111X - Fall Test 1 6/9 Computing ID:

7 CS 111X - Fall Test 1 7/9 Computing ID: store = { book1 : 12, book2 : 14, book3 : 15, book4 : 8 }

8 CS 111X - Fall Test 1 8/9 Computing ID: Scratch Paper - Nothing on this page will be graded!

9 CS 111X - Fall Test 1 9/9 Computing ID: Scratch Paper - Nothing on this page will be graded!