Why logic controls execution in Blockchain / Solidity - See It in Action

Why Logic Controls Execution in Blockchain

📖 Scenario: Imagine you are creating a simple blockchain smart contract that controls how money is sent between users. The contract must check if the sender has enough money before allowing the transfer. This is like checking if you have enough cash in your wallet before buying something.

🎯 Goal: You will build a simple smart contract logic that controls the execution of a money transfer based on the sender's balance. This teaches why logic is important to control what happens in blockchain programs.

📋 What You'll Learn

Create a dictionary called balances with exact user balances

Create a variable called transfer_amount with the exact value 50

Write an if statement that checks if the sender has enough balance

Print "Transfer successful" if the transfer can happen, else print "Insufficient balance"

💡 Why This Matters

🌍 Real World

Smart contracts on blockchains use logic to control money transfers and other actions securely.

💼 Career

Understanding how logic controls execution is key for blockchain developers writing safe and correct smart contracts.

1

DATA SETUP: Create user balances

Create a dictionary called balances with these exact entries: 'Alice': 100, 'Bob': 30, 'Charlie': 75

Blockchain / Solidity

# Create the balances dictionary with exact values
# Your code here

Need a hint?

Think of balances as a wallet for each user showing how much money they have.

2

CONFIGURATION: Set the transfer amount

Create a variable called transfer_amount and set it to 50

Blockchain / Solidity

balances = {'Alice': 100, 'Bob': 30, 'Charlie': 75}
# Set the transfer amount to 50
# Your code here

Need a hint?

This is the amount Alice wants to send.

3

CORE LOGIC: Check if transfer can happen

Write an if statement that checks if balances['Alice'] is greater than or equal to transfer_amount

Blockchain / Solidity

balances = {'Alice': 100, 'Bob': 30, 'Charlie': 75}
transfer_amount = 50
# Write if statement to check if Alice has enough balance
# Your code here

Need a hint?

This logic controls if the transfer can happen or not.

4

OUTPUT: Show the transfer result

Run the program to print the transfer result message

Blockchain / Solidity

balances = {'Alice': 100, 'Bob': 30, 'Charlie': 75}
transfer_amount = 50
if balances['Alice'] >= transfer_amount:
    print("Transfer successful")
else:
    print("Insufficient balance")
# Run the program to see the output
# Your code here

Need a hint?

You should see the message that tells if the transfer can happen.