Module 3

Question 1

What data type is the following?

(10, 20)

Answer 1

Tuple

Question 2

What is the result of this comparison?

2 == 2.0

Answer 2

True

Question 3

What is the difference between these two operators?

“=“
“==“

Answer 3

= is the assignment operator. It assigns a value to a variable

== is the equality operator. It compares two values

Question 4

What is this operator or and what does it do?

!=

Answer 4

The not equal operator. This checks whether two values or expressions are not equal to each other

It is a binary operator.

Returns a Boolean value

Question 5

What is this operator?

<=

Answer 5

Less than or equal to

Question 6

What is this operator? And what does it do?

> =

Answer 6

Greater than or equal to

It is a binary operator
It compares values on either side of it

It has left side binding

Question 7

As far as priority goes, where do the greater than, less than, greater than or equal to, and less than or equal to operators sit in the spectrum?

Answer 7

They are below binary addition subtraction operators and above the equality and not equal operators

Question 8

What is a group of if-elif-else statements called?

Answer 8

A cascade

Question 9

What does the max() function do?

Answer 9

Finds the largest number out of multiple arguments or an iterable

Question 10

List the comparison operators

Answer 10

== equal
!= not equal
> Greater than
< Less than
>= greater than or equal to
<= less than or equal to

Question 11

Are comparison operators binary?

Answer 11

Yes

Question 12

Do uppercase letters have a higher ASCII value than lowercase letters?

Answer 12

No

In fact, lowercase letters have a higher value than their uppercase counterparts

Question 13

A number corresponding to a character is called a:

Answer 13

Codepoint

Question 14

can len() return the value of an int or a float?

Answer 14

No

Question 15

What is the output of this code?

x = 10

if x == 10:
print(x == 10)
if x > 5:
print(x > 5)
if x < 10:
print(x < 10)
else:
print(“else”)

Answer 15

True
True
else

all If statements are evaluated

The final code block is an If/Else statement. Since the If fails, then the Else is triggered

Question 16

What is the output of the following snippet?

x = 1
y = 1.0
z = “1”

if x == y:
print(“one”)
if y == int(z):
print(“two”)
elif x == y:
print(“three”)
else:
print(“four”)

Answer 16

one
two

Both if statements are evaluated

Since the second if belongs to an if/elif/else block, once the first if is successfully evaluated the elif and the else are skipped

Question 17

a “while” statement repeats the execution of the code inside it as long as the condition evaluates to _________

Answer 17

True

Question 18

An instruction or set of instructions executed inside the while loop is called

Answer 18

the loop’s body

Question 19

True or False?

If the “while” condition is False when it is evaluated the first time then the loop’s body is executed at least once

Answer 19

False

If the “while” condition is false when it is first evaluated, then the loop’s body is never executed

Question 20

What is another name for an Infinite Loop?

Answer 20

An Endless Loop

Question 21

What is the “for” loop designed for?

Answer 21

To browse large collections of data

Like the results of a database query

i.e.

new_row = []

for row in results:
order_num = row[1]
new_row.append(order_num)

Question 22

any variable after the “for” keyword is the __________ variable

Answer 22

control

Question 23

What does the control variable of a “for” loop do?

Answer 23

it counts the loop’s turns automatically

Question 24

Is the range() function inclusive

Answer 24

No

It is exclusive.

So, range(100) will give you all values from 0 to 99

Question 25

How many arguments can the range() function take?

Answer 25

3 If 2 arguments are provided, the first positional argument denotes the starting value, the second parameter is the ending value So, for i in range(2,8): print(i) will print these integers to the console: 2,3,4,5,6,7 if 3 arguments are provided, the third argument is the increment or "step" for i in range(2, 8, 3): print(i) will print these integers to the console: 2,5

Question 26

does the range() function accept floats as an argument?

Answer 26

no. Only integers. And it produces only integers

Question 27

The range() function only accepts _________ as arguments

Answer 27

integers

Question 28

What is the printout of the following code snippet? for i in range(2, 8, 3): print("here is:", i)

Answer 28

here is 2 here is 5

Question 29

What does the "break" keyword do inside a loop?

Answer 29

exits the loop immediately

Question 30

What does the "continue" keyword do inside a loop?

Answer 30

it behaves as if the loop execution was finished, and starts the loop over from wherever the continue keyword is accessed So for in in range(2,12, 3): if i == 5: continue print(i) will print the following to the console: 2 8 11 (Skipping 5)

Question 31

when is a loop's "else" branch executed?

Answer 31

every time - whether the while (or "for") loop's body is executed or not Unless the loop is exited by the “break” keyword

Question 32

What does the following code snippet print to the console? i = 111 for i in range(2, 1): print(i) else: print("else:", i)

Answer 32

111 the for loop's body is never executed, and (it doesn't change the i variable's value) so the else branch is executed and the value of i is printed to the console * unless the loop is broken -- as in, unless the loop is terminated by break

Question 33

What is a connection of conditions called?

Answer 33

A conjunction

Question 34

What is a logical operator that is a unary operator that performs logical negation?

Answer 34

not

Question 35

Which logical operator is known as logical negation?

Answer 35

not

Question 36

Which logical operator is known as logical conjunction?

Answer 36

and

Question 37

Which logical operator is known as logical disjunction?

Answer 37

or

Question 38

When is a loop’s else branch NOT executed?

Answer 38

If the loop’s execution is broken by the “break” keyword

Question 39

Describe how strings are compared by comparison operators

Answer 39

They are compared lexicographically Letters increase in value as they continue in the alphabet So print(“a” < “b”) == True And capital letters have a lower value than their lowercase counterparts So print(“A” < “a”) == True print("a" < "b") # True print("A" < "a") # True print("apple" < "banana") # True print("apple" < "application") # True print("apple" == "apple") # True print("Apple" < "apple") # True

Question 40

What is the printout of the following code snippet? print("apple" < "application")

Answer 40

True The strings are the same up until the letter “e” in Apple “e” has a lower lexicographic value than “I” so “apple” evaluates to less than “application”

Question 41

What is the result of this code snippet? print( "this is " + " my test Exam ".lstrip() + "woot")

Answer 41

this is my test Exam woot lstrip() only strips leading blank spaces from a string

Question 42

How to remove all items from a dictionary?

Answer 42

Use the clear() method

Question 43

What will this code snippet return? Why? alist = [3, 4, 5] print( "this one",alist[-2:8])

Answer 43

this one [4,5] String slicing doesn't care if the end index is out of range for the string. It will slice as much of the string as it can

Question 44

what is the logical conjunction operator in Python?

Answer 44

and

Question 45

When does the logical conjunction operator (and) evaluate to True?

Answer 45

When both operands are True

Question 46

When does the logical disjunction operator (or) evaluate to True?

Answer 46

When at least one of the operands are True

Question 47

How does the logical negation operator work?

Answer 47

It is a unary operator, so it only needs one operand. If the operand is True, then it makes it False If the operand is False, then it makes it True

Question 48

What is the result of this code snippet? var = 17 var_right = var >> 1 print(var_right)

Answer 48

8 the right shift operator halves the left operand by the amount of the right operand It is, essentially, working as integer division. in this case 17/2 = 8.5, rounded down (floor) = 8

Question 49

Okay, smart guy, what is the result of this code snippet? What is the result of this code snippet? var = 18 var_right = var >> 3 print(var_right)

Answer 49

2 18 / 2 = 9 9 / 2 = 4.5 (floor = 4) 4 / 2 = 2

Question 50

What is the output of this code snippet? x = 1 y = 0 z = ((x == y) and (x == y)) or not(x == y) print(not(z))

Answer 50

False Left Side Operand: ( ( x == y ) and ( x == y ) ) ---> False logical and only evaluates to True if both operands evaluate to True Since both operands in this case are False, then the logical and evaluates to False Right Side Operand: not( x == y) ---> True Logical negation always changes the Truthiness of its operand. So, since x == y is False, then the logical negation changes it to True or The logical or evoluates to True, so long as one of its operands is True So, since the left side operands is False and the right side operand is True, then the logical or evaluates to True So.... z == True And finally, the print applies a logical negation to var z (which is True), so the result is False

Question 51

How to calculate the binary value of a number?

Answer 51

repeatedly divide the number by 2 and note the remainders, then write the remainders in reverse order Ex: What is 10 in binary? 10 / 2 = 5 remainder —-> 0 5 / 2 = 2 remainder ——> 1 2 / 2 = 1 remainder ——> 0 1 / 2 = 0 remainder ——> 1 Reversing the order of remainders = 1010 which is the binary value of 10

Question 52

What is the result of this code? x = 4 y = 1 a = x & y print( a )

Answer 52

0 x = 4 4 = 100 when converted to binary 4 / 2 = 2 rem 0 2 / 2 = 1 rem 0 1 / 2 = 0 rem 1 reverse the remainders and you get 100 is the binary of 4 y = 1 1 = 1 when converted to binary (0 = 0 when converted to binary) Bitwise logical conjunction requires two 1s to make a 1, so a 0 and a 1 makes a 0 So... 100 & 001 = 000 or look at it this way: 100 001 ----- 000 So... x & y = 0

Question 53

What is this operator? And what does it do? &

Answer 53

bitwise conjunction It requires two 1s to make a 1, so a 1 and a 0 = 0