List indexing and slicing in Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get the first element of the list.

Python

my_list = [10, 20, 30, 40]
first_element = my_list[[1]]
print(first_element)

Drag options to blanks, or click blank then click option'

A0

B1

C-1

D4

Attempts:

3 left

💡 Hint

Common Mistakes

Using 1 as the index to get the first element.

Using 4 which is out of range.

List indexing starts at 0, so the first element is at index 0.

2fill in blank

medium

Complete the code to get the last element of the list using negative indexing.

Python

numbers = [5, 10, 15, 20, 25]
last_num = numbers[[1]]
print(last_num)

Drag options to blanks, or click blank then click option'

A-2

B4

C0

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Using -2 which gives the second last element.

Using 0 which is the first element.

Negative indexing starts from the end. -1 is the last element.

3fill in blank

hard

Fix the error in the code to slice the list and get elements from index 1 to 3 (inclusive of 1, exclusive of 4).

Python

letters = ['a', 'b', 'c', 'd', 'e']
sublist = letters[[1]]
print(sublist)

Drag options to blanks, or click blank then click option'

A1-4

B1,4

C1:4

D1..4

Attempts:

3 left

💡 Hint

Common Mistakes

Using commas or dashes instead of colon in slicing.

Using '..' which is not valid syntax.

List slicing uses colon ':' to specify start and end indexes.

4fill in blank

hard

Fill both blanks to slice the list and get every second element from index 0 to 5.

Python

data = [2, 4, 6, 8, 10, 12, 14]
slice_result = data[[1]:[2]:2]
print(slice_result)

Drag options to blanks, or click blank then click option'

A0

B5

C6

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using 6 as end index which includes index 5 element.

Using 1 as start index which skips the first element.

The slice data[0:5:2] gets elements at indexes 0, 2, and 4.

5fill in blank

hard

Fill both blanks to create a dictionary with words as keys and their lengths as values, but only for words longer than 3 letters.

Python

words = ['apple', 'bat', 'carrot', 'dog']
lengths = {: [1] for [2] in words if len(word) > 3}

Drag options to blanks, or click blank then click option'

Aword

Blen(word)

D{

Attempts:

3 left

💡 Hint

Common Mistakes

Not starting with '{' which causes syntax error.

Using 'word' twice incorrectly for key and loop variable.

The dictionary comprehension syntax is {key: value for item in iterable if condition}.