Spring Semester 11 Exam #1 Dr. Dillon. (02/15)

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1 Spring Semester 11 Exam #1 Dr. Dillon. (02/15) Form 1 A Last name (printed): First name (printed): Directions: a) DO NOT OPEN YOUR EXAM BOOKLET UNTIL YOU HAVE BEEN TOLD TO BEGIN. b) You may use one 8.5" x 11" note sheet during the exam. No other reference materials or electronic devices may be used during the examination. c) Questions will not be interpreted during the examination. You should choose the single best alternative for each question, even if you believe that a question has multiple correct answers, is ambiguous or contains a typographic error. d) Write your name at the top of this exam booklet and on the answer sheet for the coding problem. e) Use a #2 pencil to encode information on the OMR form: Last name and first initial MSU PID Exam form: 1A Answers to the multiple choice questions f) Sign the OMR form. g) Only answers recorded on your OMR form will be counted for credit for multiplechoice questions. Completely erase any responses that you wish to delete. h) You have 80 minutes to complete the exam. This exam booklet contains 26 multiple choice questions, each weighted equally (5 points) and two programming problems (totaling 20 points). (28 questions, 8 total pages) i) Turn in this exam booklet, your note sheet, your scratch paper, and the OMR form when you are done. Write your name on anything you would like returned to you after the exam is graded. When leaving, please be courteous to those still taking the exam. Good luck! Timing tip. A rate of 2.5 minutes per multiple choice problem leaves 15 minutes to write the program (worth 20 points) at the end ********* Form A A C B B B B D C C A C D B A D C D C C A B D D C A D 01:b, 02:b, 03:c, 04:c, 05:a, 06:d, 07:b, 08:d, 09:d, 10:b,

2 1) Which of the following is incorrect? a) A method in Python cannot modify the object that it applies to. b) A module in Python consists of a list of commands. c) A program that has a syntax error cannot be run. d) The main semantic difference between lists and tuples in Python is that tuples are immutable and lists are mutable. (i.e., all are correct) 2) Assume the variable v references a string of digits. Then what does executing int(v)do? a) Assigns v the integer represented by this string, and does not return anything. b) Assigns v the integer represented by this string, and returns the integer. c) Returns the integer represented by this string (without modifying v). d) None of the above. 3) What is returned by range(100)[5]? a) 4 b) 5 c) [0, 1, 2, 3, 4] d) [1, 2, 3, 4, 5] 4) What is returned by range(50,100)[-5:]? a) [100, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50] b) [95, 96, 97, 98, 99] c) [96, 97, 98, 99, 100] d) 95 5) Given A = True and B = False, what is returned by A!= (not B)? a) True b) False c) An error message d) Nothing. 6) Given v = 22 and w = 3, which statement about the command below is true? if 0 < (v % 5) < w: print 5 else: print 4 a) The command prints 4 b) The command prints 5 c) A syntax error prevents the command from being run. d) An error occurs when the command is run.. 7) Given x = 0 and y = 1, what is returned by (y or (y/x))?

3 a) False b) True c) 0 d) 1 8) Given x = 2 and y = 5, what is returned by (y and x)? a) True b) False c) 2 d) 5 9) Given s = The early bird gets the worm. What is returned by s[5]? a) e b) The e c) a d) arly bird gets the worm. 10) Given s = The early bird gets the worm. What is returned by s[-5]? a) w b) c) e d). sdy 11) Given s = The early bird gets the worm. What is returned by s[4:8]? a) ear b) earl c) earl d) early 12) Given s = The early bird gets the worm. What is returned by s[::-5]? a) worm. b).mrow c) w d). sdy

4 Figure 1 13) Given user input of 6, what output is produced by Line 3 in Figure 1? a) 6 b) 7 c) 8 d) 9 e) None of (a) (d) 14) Given user input of 6, what output is produced by Line 4 in Figure 1? a) 6 b) 7 c) 8 d) 9 e) None of (a) (d) 15) Given user input of 6, what output is produced by Line 5 in Figure 1? a) 6 b) 4 c) 2 d) 0 e) None of (a) (d) 16) Given user input of 6, how many times is the Boolean expression in Line 1 in Figure 1 evaluated? a) 6 b) 4 c) 2 d) 0 e) None of (a) (d) 17) Given user input of 6, how many times is the command in Line 2 in Figure 1 executed? a) 4 b) 3 c) 2 d) 1 e) None of (a) (d) 18) Given that n references a positive integer, which code prints the factorial of n?

5 Figure 2 19) What output is produced by Line 1 in Figure 2? a) [ 5, 2, 3 ] b) 10 c) 523 d) ) What output is produced by Line 2 in Figure 2? a) [] b) [ 5, 2, 3 ] c) [ 3, 2, 5 ] d) False 21) What output is produced by Line 3 in Figure 2? a) <type str > <type list > b) <type list > <type str > c) <type list > <type list > d) <type bool > <type str > 22) Given: x, y, z = Hello, range(0,6,3), ( a, 1) Which of the following will not produce an error? a) x[0] = j b) x + y c) z[1] += 1 d) z = z[1] + 1 (i.e., all will produce an error) 23) Which of the following is correct? a) In Python, a string cannot be modified. b) In Python, a string can be used in creating another string. c) In Python, the type of a variable can change during execution of a program. d) All of the above..

6 Figure 3 24) What output is produced by Line 1 in Figure 3? a) M b) MP c) Monty d) An error 25) What output is produced by Line 2 in Figure 3? a) P b) Python c) n d) An error 26) What output is produced by Line 3 in Figure 3? a) Doe, J.: 1.25 b) Doe,J.:1.25 c) Doe, J. : 1 d) Doe,J.:1.250

7 Please, write on scrap paper first; then copy your answers to the (blue) written-problems solution sheet handed out with the exam. Make sure you put your name on the (blue) solution sheet and hand it in at the end of the test. Notes Your programs must work as described in the Requirements for full credit. Your programs do not need extensive comments; but if there is a tricky bit of code, a comment can help the grader see what you mean to do (which can help in case of errors to justify partial credit). Readability does matter. Make it readable! Do it on scrap paper first! Be clear about your indentation! Write legibly!! 27) Program question #1 (12 pts) Requirements Your program will repeatedly prompt the user to type a saying with between 3 and 20 characters or a q to quit. The program will print a message notifying the user if the saying is legal or not and then prompt for the next saying. When the user inputs either Q or q, the program will print the total number of (legal) sayings, their total number of characters (lengths), and their average length. The average is to be printed with one decimal digit of precision. For the purpose of this first program, a legal saying is any string with between 3 and 20 characters (inclusive). (Remember, whitespace and punctuation count as characters.) See below for an example interaction. Example interaction

8 28) Program question #2. (8 pts) Do the same problem as #27, except: In each saying, replace blank spaces with underscores. For example, the saying Monty Python rules! becomes Monty_Python_rules! Instead of calculating and printing the totals and average, print a 3-column table of the legal sayings, as shown in the example interaction below. The width of each column is 22 characters the saying is right justified in a field of width 20 and there is one space between this field and the separator mark ( ) on either side. The table title is centered over the table. All rows, except possibly the last, have 3 sayings. Notes and Hints Recall the replace method for strings: s.replace(old, new) returns a string from s by replacing the substring old with new. For example: o aba bab.replace( ab, x ) -> xa bx o bill.txt.replace(., ) -> billtxt Recall the center method for strings: s.center(width) returns a string of length width with s centered; by default, the string is filled with blank spaces. For example: o aba.center(10) -> aba Example interaction