Computer Science 111 Final Exam

The comparison operators are A. ==, <, >, <=, >=, and != B. and, or, and not C. +, -, *, and /

A. ==, <, >, <=, >=, and !=

A finite sequence of computable steps that halts with a solution to a problem is called a(n) ____

Algorithm

Consider the code segment name = "Ken Lambert" To access the letter "t" in name, you would use the expression ____ A. name[len(name)] B. name[len(name) - 1]

B. name[len(name) - 1]

The {while} loop stops iterating when its condition becomes ____

False

The / operator returns a value of type ____

Float

The code segment "3" + "5" evaluates to the value ____

"35" - got wrong on quiz

To convert the string "Computer" to uppercase, you would use the expression ____

"Computer".upper()

The method call "ken lambert".upper() returns the string ____

"KEN LAMBERT"

Consider the code segment name = "Ken Lambert" The expression name[0:3] evaluates to the value ____

"Ken"

To open a file for output, where you intend to overwrite an existing file, you run the open function with the argument

'w'

The expression "%6d" % 43 returns a string containing ____ spaces to the right of the digits in "43"

0

The statement for x in range(1, 5, 2): print(x) outputs the numbers

1 and 3

The type of statement that gives a value to a variable is called an ____

Assignment Statement

To loop through the integers from 1 through 10, you use the loop header A. for x in range(10): B. for x in range(1, 10): C. for x in range(1, 11):

C. for x in range(1,11)

A while loop whose condition never becomes False and which contains no break statements is said to be A. definite B. indefinite C. infinite

C. infinite

Jack is modeling a process that will repeat an unpredictable number of times. The control statement that he should use in his code for this is a(n) ____ A. if/else statement B. for loop C. while loop

C. while loop

The program that translates a Python program into byte code is called the ____

Compiler

A program consists of a sequence of instructions that manipulate ____

Data

The tripple-quoted text that appears at the beginning of a Python program is called a(n) ____

Docstring

Let A be 10 and B be 2. Then, the value of the expression A <= B is ____

False

Let A be True and B be False. Then the value of the expression not A or B is ____

False

Let A be True and B be False. Then, the value of the expression A and B is ____

False

The data type that represents numbers containing a decimal point is ____

Float

The type of statement that makes the code resources of another Python module available to a program is called an ____

Import Statement

The // operator returns a value of type ____

Int

Jack wants to process lines of text from an input file. Should he use the read method to input the text, or a for loop over each line? Justify your answer.

Jack should use a for loop, because it reads each line in the file, rather than the entire text.

The expression "%0.2f" % 3.146 returns the string ____ (remember that strings are enclosed in double or single quotes).

"3.15"

Consider the following code segment: name = "Ken Lambert" substring = "" for ch in name: if ch != " ": substring += ch The value of substring when the loop finishes is ____

"KenLambert" - got wrong on quiz

Consider the code segment name = "Ken Lambert" The expression name[4] evaluates to the value ____

"L"

The expression "Python rules!"[2:4] returns the value ____

"th"

To open a file for input, you would run the open function with the argument

'r'

The character at the first position in a non-empty string is located at the index position ____

0

The expression 5 % 2 produces the value ____

1

The expression int(3.75) produces the value ____

3

Let A be -5. Then the value of A after the statement if A < 0: A = -A is run would be ____

5

To access the letter 'h' in the string "Python", you would use the subscript ____

[3]

A set of keys associated with values.

a dictionary

A mutable sequence of items of any type.

a list

The lifetime of a parameter or a temporary variable is the duration of

a particular activation of a function or method

The Python method read inputs

a single string containing the entire text of a file

An immutable sequence of characters.

a string

A sequence of characters on a secondary storage medium.

a text file

An immutable sequence of items of any type.

a tuple

A list can contain

anything at all, including different types of things at different positions

The method that allows you to add an item to the end of a list, increasing its length by 1.

append

The scope of a temporary variable is the

area of text below where it is introduced within the body of a function definition

The values True and False belong to the data type ____

bool

The statement that exits a loop within that loop's body is called ____

break

Assume that the function choice is not defined in the random module, but that you have imported randint from that module. Define a new Python function, named choice, that expects a nonempty list as an argument and returns an item chosen from a random position in that list. The function's header is def choice(lyst):

def choice(lyst): ...........for items in lyst: ..........................return lyst[random.randint(0,len(lyst)-1)]

The literal structure {"name":"Ken", age:67, "hair color":"gray"} is an instance of a

dictionary

The Python method write

does not automatically output a newline to a file

When at least one of its two operands is of type float, an arithmetic operator produces a value of type ____

float

Assume that inputFile refers to a file opened for input and outputFile refers to a file opened for output. Write a code segment that would copy the contents of the input file to the output file. You should need only two or three lines of code (remembering to close the output file).

for lines in inputFile: outputFile.write(lines) outputfile.close()

An example of a control statement is the ____

for loop

When you attempt to open a file for input and the file does not exist, Python

halts the program by raising a runtime error

Consider the code segment total = 0 number = 1 while number <= 4: ..........total += number number += 1 print(total) This code ____

hangs in an infinite loop

Consider the code segment total = 0 number = 1 while number <= 4: ......total += number number += 1 print(total) This code ____

hangs in an infinite loop

To modify each item in a list, you must use a for loop over the list's

index positions (with a subscript)

The function that converts an input string of digits to an integer is called ____

int

The ____ method glues together the strings in a list to form one string

join

The method that glues together a list of words to form a string is called

join

A mutable data structure.

list

Jill needs to work with a set data values that are ordered by position. She does not know ahead of time how many values will be input. The appropriate data structure for organizing these values is a

list

The ____ module includes resources for performing numerical computations.

math

qualifiers = ["Why do you say that", "Please explain that"] def reply(sentence): return random.choice(qualifiers) + changePerson(sentence) In this code, qualifiers is the name of a

module variable

Unlike strings, lists are

mutable data structures

Set a variable named numbers to be a list of the numbers 1 through 100, inclusive. Hint: you may use the list and range functions.

numbers = list(range(1, 101))

Jill Is working on a program that outputs line numbers followed by the lines of text they number. She is using the variable lineNumber for the number and line for the text. She wants to output the numbered line to the terminal, with the line number right-justified in 4 columns and with two spaces between it and the line of text. The line of text does not contain a newline. Write a line of code that would print these data in this format to the terminal. (Hint: you use a format string.) format = "%4d " % lineNumber + line

print("%4d %s" % (lineNumber, line))

When you use the subscript operator [] with a key that is not present in a dictionary, Python responds by

raising a KeyError

A for loop through a dictionary accesses its keys in

random order

The method that reads a line of text from a file.

readline

In computer science, an abstraction is something that

simplifies a complex thing so we can deal with more easily

The method that returns a list of the words in a string is called

split

def getSum(low, high): .........total = 0 ..........for number in range(low, high + 1): ........................total += number return total In this code, total is the name of a

temporary variable

An immutable data structure.

string

The operator that allows you to access or modify an item at a given index position in a list.

subscript

Consider the code segment total = 0 number = 1 while number <= 4: ...........total += number ............number += 1 print(total) The output of this code is ____

10

Consider the code segment total = 0 number = 1 while number <= 4: .......total += number .......number += 1 print(total) The output of this code is ____

10

The expression 2 * 3 ** 2 produces the value ____

18

The expression 2 times 3 ** 2 produces the value ____

18

The expression 2* 3 ** 2 produces the value ____

18

The expression 5 / 2 produces the value ____

2.5

Consider the following code segment: number = 8 count = 0 while number > 0: ............count += 1 ............number = number // 2 print(count) The output of this code segment is ____

4

After the following code segment is run, the value of total is total = 0 for n in range(4): total += n

6

The function sum computes and returns the sum of a sequence of numbers, including a sequence returned by the range function. The value of the expression sum(range(4)) is ____

6

The Python operator that tests two values for equality is ____

==

When you attempt to open an input file that does not exist, what happens?

Python raises an exception and halts the program (red ink).

The ____ is a program that runs the byte code of a Python program.

Python virtual machine

Quiz 1

Quiz 1

Quiz 3

Quiz 3

The input function returns a(n) ____

String

What is the function os.path.exists used for?

This function is used to determine whether or not a file exists in the file system.

A while loop will continue execution as long as its condition is ____

True

If N is an even number, then the expression N % 2 == 0 evaluates to the value ____

True

In the code segment if b1: s1 else: s2 the statement s1 is run only if the value of the Boolean expression b1 is ____

True

Let A be True and B be False. Then, the value of the expression A or B is ____

True

The expression 'A' < 'a' returns the value ____

True

The value output by the code segment x = 10 print(x >= 0 and x <= 10) is

True