Name Feb. 14, Closed Book/Closed Notes No electronic devices of any kind! 3. Do not look at anyone else s exam or let anyone else look at yours!

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1 Name Feb. 14, 2018 CPTS 111 EXAM #1 Closed Book/Closed Notes No electronic devices of any kind! Directions: 1. Breathe in deeply, exhale slowly, and relax. 2. No hats or sunglasses may be worn during the exam. 3. Do not look at anyone else s exam or let anyone else look at yours! 4. Be neat! If we can t read what you ve written, we can t give you credit! 5. If an answer is afloat, make it clear by using a decimal point. 6. If an answer is an integer, make it clear by not using a decimal point. 7. If an answer should be in quotes, then use quotes. 8. All multiple choice questions have only one correct answer. 9. When writing code, indent clearly when you should indent. 10. When writing code, do your best to indicate what you can do even if you can t do everything. 11. Each question is worth 2 points unless otherwise indicated. 12. Read each question carefully and check your work if you finish early! 1

2 1. Which function is used to determine the type of an identifier? (a) help() (b) id() (c) eval() (d) type() 2. Consider the Python expression: 10 // 3 (a) The// operator performs [floor / float] division (circle one). (b) What is10 // 3? 3. Consider the Python expression: 10 % 3 (a) The%operator performs the (b) What is10 % 3? function/operation. 4. The scope of variables in a function is local. 5. What are the value and type ofyafter the following program executes? (a) Value: (b) Type: def divide(x): return x / 3.0 y = divide(3) 6. What is the output of the statement: print(eval( 2 ** 3 )) (a) 8 (b) 2 ** 3 (c) 2 ** 3 (d) This produces an error. 2

3 7. Ifnum dogs = 2, which of the following statements is correct? (a) print( He has %d dogs. % num dogs) (b) print( He has %e dogs. % num dogs) (c) print( He has %f dogs. % num dogs) (d) None of the above. 8. The following code will throw an exception, i.e., it will produce an error. def calc_meters(ft, inch): pass meters = calc_meters(5, 6) 9. For the following code, which function call is incorrect? def square(num): return num ** 2 (a) result = square(33.7) (b) result = square(33.7) + square(77.3) (c) result = square(square(33.7)) (d) square(33.7) 10. Fix the two errors in the following code: def add(num1, num2) sum = num1 + num2 return y = add(10001, 23456) 3

4 11. What is the value ofxafter the following code has been executed (be careful with precedence!)? x = 3 * ** 4 / 2 (a) 10 (b) 10.0 (c) 14 (d) 14.0 (e) None of the above. 12. What is the output of the following code? (a) 0 (b) 1 (c) 2 x = 1 x = x + 2 % 2 print(x) (d) It produces an error. 13. print() doesn t return anything, andreturn doesn t print anything. 14. Scope resolution is the process of searching for names in namespaces. The interpreter first looks in local namespace, then in global namespace, and finally in built-in namespace. 15. docstrings are used in functions to briefly describe what they do. They re written using the pound sign also known as a hashtag or octothorpe. 4

5 16. When the following code is executed, the user enters 10 at the prompt. What is the resulting type of the variablex? (a) float (b) str (c) int x = input( Enter x: ) (d) This produces an error. 17. When the following code is executed, the user enters10.0 at the prompt. What is the resulting type of the variablex? (a) float (b) str (c) int x = int(input( Enter x: )) (d) This produces an error. 18. When the following code is executed, the user enters10.0 at the prompt. What is the resulting type of the variablex? (a) float (b) str (c) int x = int(float(input( Enter x: ))) (d) This produces an error. 19. Which of the following will produce an error? (a) int(3.2) (b) str(3.2) (c) float( 3.2 ) (d) int( 3.2 ) (e) None of the above. 5

6 20. Which of the following isn t a valid name for a variable or function? (a) foo-bar (b) foobar (c) foo bar (d) FOOBAR (e) They re all valid. 21. What are the values ofxandy, respectively, after the following code is executed? (a) 1 and7 x = 12 y = 7 x, y = divmod(x, y) (b) 1.0 and7 (c) 1 and5 (d) 1.0 and5 (e) None of the above. 22. What is the output of the following code? Print it carefully under the code. >>> print( 3\n2\n1\nTake off! ) 23. Your Python code doesn t run at all because of an error. What is the most likely type of error? (a) A problem with your logic, i.e., a bug in your code. (b) A run-time error. (c) A syntax error. (d) None of the above. 6

7 24. How many bits does it take to represent 8 unique items? (a) 2 (b) 3 (c) 4 (d) 8 (e) None of the above. 25. Which literal is most accurately represented in Python? (a) (b) 3.14e12 (c) (d) They re all equally accurately represented in Python : The following code is executed: x = 5 a = int(x + 1 / 3) b = * x c = x ** What are the values of the following variables? Don t forget to use decimal points to indicate float values. 26. a = 27. b = 28. c = 29. [3 pts] Write a single Python statement to obtain the following output: 1 Hello, World! 30. [3 pts] Write a single Python statement to obtain someone s first name using the following prompt: 1 What s your first name? 7

8 31. [3 pts] Write a single Python statement that will print I owe you $ if amount = [4 pts] You are given the following code: 1 exchange_rate = def convert(dollars): 4 euros = dollars * exchange_rate 5 print( Hello from convert()! ) 6 return euros def main(): 9 print( Hello from main()! ) main() There are somw problems with the code above. Answer the following regarding this code: (a) exchange_rate is a [local variable / global variable] (circle one) (b) euros is a [local variable / global variable] (circle one) (c) Hello from convert()! will be printed when this code is executed [true / false] (circle one) (d) Hello from main()! will be printed when this code is executed [true / false] (circle one) 33. [3 pts each] Correct the code above by adding three lines tomain(), one that prompts a user for the number of dollars, one that callsconvert(), and one that prints the result of calling convert() together with the statementtotal euros are: 8

9 34. [4 pts] Define a void functioncoug fan() that printsgo, Cougs! It has no parameters : In the following three problems you need to write three functions that are related to each other. The first isget input(). The second issum nums, and the third ismain() which calls the other two functions. 35. [6 pts] Define a non-void function get input() which first prompts a user for an integer number and then prompts the user for a float number. It then returns these values tomain(). 36. [4 pts] Define a non-void functionsum nums() with two parameters passed to it. It adds these two parameters and returns the result tomain(). 37. [8 pts] Define void function main() that calls a function get input() which returns num1 and num2. These values are then passed to a function called sum nums() which returns total. This result is then printed inmain(). 9