Practice Questions for Dictionary and sets

Practice Questions for Dictionary and sets#

Initialize Empty Dictionary and Empty Set (Correct and Exam-Safe)#

# Empty dictionary
d = {}

# Empty set (important: {} creates a dictionary, not a set)
s = set()

print(type(d))
print(type(s))

Output

<class 'dict'>
<class 'set'>
⏳ Loading Pyodide…

A. Basic Level (10 Questions)#

Dictionary – Basic#

1. Create and access

Output

Alice

2. Add a new key-value pair

Output

{'id': 101, 'marks': 90}

3. Update a value

Output

{'apple': 120}

4. Get keys

Output

dict_keys(['a', 'b'])

5. Get values

Output

dict_values([10, 20])

Set – Basic#

6. Create a set

Output

{1, 2, 3}

7. Add element to set

Output

{1, 2, 3}

8. Remove element

Output

{1, 3}

9. Set length

Output

3

10. Membership test

Output

True

B. Intermediate Level (10 Questions)#

Dictionary – Intermediate#

1. Iterate through dictionary

Output

a 1
b 2

2. Use get()

Output

0

3. Count frequency

Output

{'a': 2, 'b': 2, 'c': 1}

4. Dictionary comprehension

Output

{1: 1, 2: 4, 3: 9}

5. Merge dictionaries

Output

{'a': 1, 'b': 2}

Set – Intermediate#

6. Union

Output

{1, 2, 3}

7. Intersection

Output

{2, 3}

8. Difference

Output

{1, 3}

9. Subset check

Output

True

10. Remove duplicates from list

Output

[1, 2, 3]

C. Expert Level (5 Questions)#

1. Invert a dictionary

Output

{1: ['a', 'c'], 2: ['b']}

2. Find common values across dictionaries

Output

{2}

3. Remove keys with duplicate values

Output

{'a': 1, 'b': 2}

4. Group words by length

Output

{2: ['hi', 'by'], 5: ['hello'], 6: ['python']}

5. Find symmetric difference of multiple sets

Output

{1, 4}

Daily-Life Based Advanced Questions (5)#

Each problem reflects a realistic scenario, uses dictionary and/or set, and includes input + output code.

Q1. Student Attendance Tracker (Deduplication + Count)#

Problem A teacher records roll numbers of students who entered the class multiple times. Remove duplicates and count total unique attendees.

Output

Unique students: {101, 102, 103, 104}
Total present: 4

Q2. Expense Categorization (Daily Spending)#

Problem You track daily expenses and want total spending per category.

Output

{'food': 200, 'travel': 80, 'shopping': 200}

Q3. Common Friends Between Two People (Social Media)#

Problem Find mutual friends between two users.

Output

{'Amit', 'Sneha'}

Q4. Product Purchase Frequency (E-commerce)#

Problem An online store wants to know how many times each product was purchased.

Output

{'phone': 3, 'laptop': 2, 'tablet': 1}

Q5. Identify Unique Visitors Across Multiple Days (Website Analytics)#

Problem Each day’s website visitors are logged. Find total unique visitors.

Output

Unique visitors: {1, 2, 3, 4, 5, 6, 7, 8}
Total visitors: 8
Contents