Layer 2 solutions overview in Blockchain / Solidity - Mini Project: Build & Apply

Layer 2 Solutions Overview

📖 Scenario: You are working with blockchain data and want to organize information about Layer 2 solutions. Layer 2 solutions help blockchains handle more transactions quickly and cheaply by working on top of the main blockchain.

🎯 Goal: You will create a dictionary of Layer 2 solutions with their types, set a filter type, extract solutions of that type using dictionary comprehension, and finally print the filtered solutions.

📋 What You'll Learn

Create a dictionary called layer2_solutions with exact entries for solutions and their types

Create a variable called filter_type with the exact string value to filter solutions

Use dictionary comprehension to create a new dictionary called filtered_solutions containing only solutions matching filter_type

Print the filtered_solutions dictionary

💡 Why This Matters

🌍 Real World

Layer 2 solutions are important in blockchain to improve speed and reduce costs. Organizing and filtering these solutions helps developers and users understand options available.

💼 Career

Understanding how to manage and filter data structures like dictionaries is essential for blockchain developers working with Layer 2 technologies and other blockchain data.

1

Create the Layer 2 solutions dictionary

Create a dictionary called layer2_solutions with these exact entries: 'Optimism': 'Optimistic Rollup', 'Arbitrum': 'Optimistic Rollup', 'Polygon': 'Sidechain', 'zkSync': 'ZK Rollup', 'Loopring': 'ZK Rollup'

Blockchain / Solidity

# Create the layer2_solutions dictionary with given entries
# Your code here

Need a hint?

Use curly braces {} to create a dictionary with keys and values separated by colons.

2

Set the filter type

Create a variable called filter_type and set it to the string 'Optimistic Rollup'

Blockchain / Solidity

layer2_solutions = {
    'Optimism': 'Optimistic Rollup',
    'Arbitrum': 'Optimistic Rollup',
    'Polygon': 'Sidechain',
    'zkSync': 'ZK Rollup',
    'Loopring': 'ZK Rollup'
}
# Set filter_type to 'Optimistic Rollup'
# Your code here

Need a hint?

Assign the string 'Optimistic Rollup' to the variable filter_type.

3

Filter solutions by type using dictionary comprehension

Use dictionary comprehension to create a new dictionary called filtered_solutions that contains only the entries from layer2_solutions where the value equals filter_type

Blockchain / Solidity

layer2_solutions = {
    'Optimism': 'Optimistic Rollup',
    'Arbitrum': 'Optimistic Rollup',
    'Polygon': 'Sidechain',
    'zkSync': 'ZK Rollup',
    'Loopring': 'ZK Rollup'
}
filter_type = 'Optimistic Rollup'
# Create filtered_solutions dictionary with comprehension
# Your code here

Need a hint?

Use a dictionary comprehension with a condition to filter by filter_type.

4

Print the filtered solutions

Write a print statement to display the filtered_solutions dictionary

Blockchain / Solidity

layer2_solutions = {
    'Optimism': 'Optimistic Rollup',
    'Arbitrum': 'Optimistic Rollup',
    'Polygon': 'Sidechain',
    'zkSync': 'ZK Rollup',
    'Loopring': 'ZK Rollup'
}
filter_type = 'Optimistic Rollup'
filtered_solutions = {solution: typ for solution, typ in layer2_solutions.items() if typ == filter_type}
# Print the filtered_solutions dictionary
# Your code here

Need a hint?

Use print(filtered_solutions) to show the filtered dictionary.