Coursera课程Python for everyone：chapter10

Chapter 10 Quiz

10 试题

1. 

What is the difference between a Python tuple and Python list?

Lists are mutable and tuples are not mutable

Lists maintain the order of the items and tuples do not maintain order

Tuples can be expanded after they are created and lists cannot

Lists are indexed by integers and tuples are indexed by strings

2. 

Which of the following methods work both in Python lists and Python tuples?

pop()

index()

sort()

reverse()

append()

3. 

What will end up in the variable y after this code is executed?

x , y = 3, 4

A two item tuple

3

4

A dictionary with the key 3 mapped to the value 4

A two item list

4. 

In the following Python code, what will end up in the variable y?

x = { 'chuck' : 1 , 'fred' : 42, 'jan': 100}y = x.items()

A list of strings

A list of tuples

A list of integers

A tuple with three integers

5. 

Which of the following tuples is greater than x in the following Python sequence?

x = (5, 1, 3)if ??? > x :   ...

(6, 0, 0)

(5, 0, 300)

(0, 1000, 2000)

(4, 100, 200)

6. 

What does the following Python code accomplish, assuming the c is a non-empty dictionary?

tmp = list()for k, v in c.items() :    tmp.append( (v, k) )

It computes the largest of all of the values in the dictionary

It computes the average of all of the values in the dictionary

It sorts the dictionary based on its key values

It creates a list of tuples where each tuple is a value, key pair

7. 

If the variable data is a Python list, how do we sort it in reverse order?

data.sort(reverse=True)

data.sort.reverse()

data = sortrev(data)

data = data.sort(-1)

8. 

Using the following tuple, how would you print 'Wed'?

days = ('Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun')

print days[2]

print days{2}

print days(2)

print days[1]

print days.get(1,-1)

9. 

In the following Python loop, why are there two iteration variables (k and v)?

c = {'a':10, 'b':1, 'c':22}for k, v in c.items() :    ...

Because the items() method in dictionaries returns a list of tuples

Because for each item we want the previous and current key

Because there are two items in the dictionary

Because the keys for the dictionary are strings

10. 

Given that Python lists and Python tuples are quite similar - when might you prefer to use a tuple over a list?

For a list of items you intend to sort in place

For a list of items that want to use strings as key values instead of integers

For a list of items that will be extended as new items are found

For a temporary variable that you will use and discard without modifying