User, Group, Expense classes in LLD - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare the User class with an __init__ method.

LLD

class User:
    def __init__(self, name):
        self.name = [1]

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

AUser

Bname

Cself

Dgroup

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning self to self.name

Using class name instead of parameter

Using undefined variable

The __init__ method assigns the parameter name to the instance variable self.name.

2fill in blank

medium

Complete the code to add an expense to the Group's expenses list.

LLD

class Group:
    def __init__(self):
        self.expenses = []
    def add_expense(self, expense):
        self.expenses.[1](expense)

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

Ainsert

Badd

Cappend

Dextend

Attempts:

3 left

💡 Hint

Common Mistakes

Using add (not a list method)

Using extend (adds multiple elements)

Using insert (requires index)

The append method adds a single item to the end of a list.

3fill in blank

hard

Fix the error in the Expense class constructor to correctly assign amount.

LLD

class Expense:
    def __init__(self, amount):
        self.amount = [1]

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

Aamount

Bself.amount

CExpense.amount

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning self.amount to self.amount

Using class name instead of parameter

Assigning zero instead of parameter

The constructor should assign the parameter amount to the instance variable self.amount.

4fill in blank

hard

Fill both blanks to create a method in Group that calculates total expenses.

LLD

class Group:
    def __init__(self):
        self.expenses = []
    def total_expense(self):
        return sum(expense.[1] for expense in self.[2])

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

Aamount

Bexpenses

Ccost

Dusers

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong attribute name

Iterating over wrong list

Using users instead of expenses

The method sums the amount attribute of each expense in the expenses list.

5fill in blank

hard

Fill all three blanks to create a method in User that adds a group and records the user's name.

LLD

class User:
    def __init__(self, name):
        self.name = name
        self.groups = []
    def join_group(self, group):
        self.groups.[1](group)
        print(f"[2] joined [3]")

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

Aappend

Bself.name

Cgroup.name

Dadd

Attempts:

3 left

💡 Hint

Common Mistakes

Using add instead of append

Printing wrong variables

Not updating groups list

The method appends the group to the user's groups list and prints a message with the user's name and group's name.