If-else statements in Blockchain / Solidity - Mini Project: Build & Apply

Simple Blockchain Transaction Approval

📖 Scenario: You are building a simple blockchain transaction approval system. Each transaction has an amount, and you want to approve or reject it based on a limit.

🎯 Goal: Build a program that checks if a transaction amount is within the allowed limit using if-else statements and prints whether the transaction is approved or rejected.

📋 What You'll Learn

Create a variable called transaction_amount with the value 150.

Create a variable called approval_limit with the value 200.

Use an if-else statement to check if transaction_amount is less than or equal to approval_limit.

Print "Transaction approved" if the condition is true, otherwise print "Transaction rejected".

💡 Why This Matters

🌍 Real World

Blockchain systems often need to approve or reject transactions based on rules like limits or balances.

💼 Career

Understanding if-else statements is essential for writing smart contracts and blockchain transaction logic.

1

Set the transaction amount

Create a variable called transaction_amount and set it to 150.

Blockchain / Solidity

# Create a variable called transaction_amount and set it to 150
# Your code here

Need a hint?

Use the equals sign = to assign the value 150 to transaction_amount.

2

Set the approval limit

Create a variable called approval_limit and set it to 200.

Blockchain / Solidity

transaction_amount = 150
# Create a variable called approval_limit and set it to 200
# Your code here

Need a hint?

Use the equals sign = to assign the value 200 to approval_limit.

3

Check if transaction is within limit

Use an if-else statement to check if transaction_amount is less than or equal to approval_limit. Use the variables transaction_amount and approval_limit exactly.

Blockchain / Solidity

transaction_amount = 150
approval_limit = 200
# Use if-else to check if transaction_amount <= approval_limit
# Your code here

Need a hint?

Use if transaction_amount <= approval_limit: to start the condition. Use else: for the other case.

4

Print the result

Print the variable result to show if the transaction is approved or rejected.

Blockchain / Solidity

transaction_amount = 150
approval_limit = 200
if transaction_amount <= approval_limit:
    result = "Transaction approved"
else:
    result = "Transaction rejected"
# Print the result variable
# Your code here

Need a hint?

Use print(result) to show the message.