Lists, Maps, and Sets in Flutter - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a list of strings named fruits.

Flutter

List<String> fruits = [1];

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

A["apple", "banana", "cherry"]

B("apple", "banana", "cherry")

C{"apple", "banana", "cherry"}

D<"apple", "banana", "cherry">

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses () instead of square brackets []

Using curly braces {} which create sets or maps

Using angle brackets <> which are for generics, not collections

In Dart, lists are created using square brackets [].

2fill in blank

medium

Complete the code to access the value for key 'name' in the map.

Flutter

Map<String, String> person = {"name": "Alice", "city": "Paris"};
String name = person[1];

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

A[0]

B["name"]

C.name

D("name")

Attempts:

3 left

💡 Hint

Common Mistakes

Using dot notation which does not work for map keys

Using parentheses which is invalid syntax

Using an index number which is for lists, not maps

To get a value from a map by key, use square brackets with the key as a string.

3fill in blank

hard

Fix the error in the code to add an item to the set.

Flutter

Set<int> numbers = {1, 2, 3};
numbers[1](4);

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

Apush

Bappend

Cadd

Dinsert

Attempts:

3 left

💡 Hint

Common Mistakes

Using append or push which are list methods

Using insert which is not a method for sets

Trying to add items with assignment instead of a method

Sets use the add() method to add new items.

4fill in blank

hard

Fill both blanks to create a map from a list of keys and a list of values.

Flutter

List<String> keys = ["a", "b", "c"];
List<int> values = [1, 2, 3];
Map<String, int> map = Map.fromIterables([1], [2]);

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

Akeys

Bvalues

Citems

Delements

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping keys and values

Using undefined variables like items or elements

Passing only one argument instead of two

Map.fromIterables takes two iterables: one for keys and one for values.

5fill in blank

hard

Fill all three blanks to create a set from a list and add a new item.

Flutter

List<int> nums = [1, 2, 3];
Set<int> numSet = [1](nums);
numSet.[2](4);
bool hasFour = numSet.[3](4);

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

ASet.from

Badd

Ccontains

DList.of

Attempts:

3 left

💡 Hint

Common Mistakes

Using List.of instead of Set.from

Using wrong method names like insert or push

Checking membership with wrong methods

Use Set.from to create a set from a list, add() to add an item, and contains to check membership.