Efficient data structures in Blockchain / Solidity - Mini Project: Build & Apply

Efficient Data Structures in Blockchain

📖 Scenario: You are building a simple blockchain ledger to store transactions. Each transaction has a unique ID and an amount. Efficient data storage is important to quickly find and update transactions.

🎯 Goal: Create a dictionary to store transactions, add a threshold to filter large transactions, use dictionary comprehension to select only large transactions, and print the filtered transactions.

📋 What You'll Learn

Create a dictionary called transactions with exact transaction IDs and amounts

Create a variable called threshold with the value 1000

Use dictionary comprehension with transaction_id and amount to select transactions with amounts greater than threshold

Print the filtered dictionary called large_transactions

💡 Why This Matters

🌍 Real World

Blockchains store many transactions and need fast ways to find important data like large transfers.

💼 Career

Understanding efficient data structures helps blockchain developers optimize storage and speed in real applications.

1

Create the transactions dictionary

Create a dictionary called transactions with these exact entries: 'tx1001': 500, 'tx1002': 1500, 'tx1003': 700, 'tx1004': 2500, 'tx1005': 300

Blockchain / Solidity

# Create the transactions dictionary with given transaction IDs and amounts
# Your code here

Need a hint?

Use curly braces {} to create a dictionary with keys as transaction IDs and values as amounts.

2

Set the threshold for large transactions

Create a variable called threshold and set it to 1000

Blockchain / Solidity

transactions = {'tx1001': 500, 'tx1002': 1500, 'tx1003': 700, 'tx1004': 2500, 'tx1005': 300}
# Create a variable called threshold and set it to 1000
# Your code here

Need a hint?

Just assign the number 1000 to the variable threshold.

3

Filter large transactions using dictionary comprehension

Use dictionary comprehension with transaction_id and amount to create a new dictionary called large_transactions that contains only transactions where amount > threshold

Blockchain / Solidity

transactions = {'tx1001': 500, 'tx1002': 1500, 'tx1003': 700, 'tx1004': 2500, 'tx1005': 300}
threshold = 1000
# Use dictionary comprehension to filter transactions greater than threshold
# Your code here

Need a hint?

Use {key: value for key, value in dict.items() if condition} to filter the dictionary.

4

Print the filtered large transactions

Write print(large_transactions) to display the dictionary of large transactions

Blockchain / Solidity

transactions = {'tx1001': 500, 'tx1002': 1500, 'tx1003': 700, 'tx1004': 2500, 'tx1005': 300}
threshold = 1000
large_transactions = {transaction_id: amount for transaction_id, amount in transactions.items() if amount > threshold}
# Print the large_transactions dictionary
# Your code here

Need a hint?

Use the print() function to show the filtered dictionary.