Balance checking in Blockchain / Solidity - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get the balance of an account.

Blockchain / Solidity

balance = blockchain.get_balance([1])

Drag options to blanks, or click blank then click option'

Awallet_key

Bblock_number

Caccount_address

Dtransaction_id

Attempts:

3 left

💡 Hint

Common Mistakes

Using block number instead of account address

Using transaction ID instead of account address

The get_balance function requires the account_address to return the balance of that account.

2fill in blank

medium

Complete the code to check if the balance is greater than zero.

Blockchain / Solidity

if balance [1] 0:
    print('Balance is positive')

Drag options to blanks, or click blank then click option'

A<

B>

C==

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using < instead of >

Using == which checks equality, not greater than

To check if the balance is positive, use the greater than operator > to compare with zero.

3fill in blank

hard

Fix the error in the code to correctly fetch the balance.

Blockchain / Solidity

balance = blockchain.[1](account_address)

Drag options to blanks, or click blank then click option'

Aretrieve_balance

Bbalance_of

Cfetch_balance

Dget_balance

Attempts:

3 left

💡 Hint

Common Mistakes

Using method names that do not exist in the blockchain API

Typo in method name

The correct method to get the balance is get_balance. Other options are invalid method names.

4fill in blank

hard

Fill both blanks to create a dictionary of account balances for accounts with balance greater than 100.

Blockchain / Solidity

balances = {account: blockchain.[1](account) for account in accounts if blockchain.[2](account) > 100}

Drag options to blanks, or click blank then click option'

Aget_balance

Bfetch_balance

Dretrieve_balance

Attempts:

3 left

💡 Hint

Common Mistakes

Using different method names for fetching balance

Using a method that does not exist

Use get_balance consistently to fetch balances in both places.

5fill in blank

hard

Fill all three blanks to create a dictionary of uppercase account names and their balances if balance is above 50.

Blockchain / Solidity

result = {account.[1](): blockchain.[2](account) for account in accounts if blockchain.[3](account) > 50}

Drag options to blanks, or click blank then click option'

Aupper

Bget_balance

Dfetch_balance

Attempts:

3 left

💡 Hint

Common Mistakes

Using inconsistent method names for balance fetching

Using wrong string method for uppercase

Use upper() to convert account names to uppercase and get_balance to fetch balances consistently.