[Solved] Identify the bug in this balance calculation code snippet:balance = 50 transactions = [10, -20, 15] for t in transactions: balance = t print(balance) | LLD

LLD - Design — Splitwise (Expense Sharing)

Identify the bug in this balance calculation code snippet:

balance = 50
transactions = [10, -20, 15]
for t in transactions:
    balance = t
print(balance)

AThe initial balance is not set

BThe transactions list is empty

CThe balance is overwritten instead of updated

DThe loop variable is incorrect

Step-by-Step Solution

Solution:

Step 1: Analyze the loop operation
Inside the loop, balance = t overwrites balance each time instead of adding.
Step 2: Understand correct update
It should be balance += t to add each transaction to balance.
Final Answer:
The balance is overwritten instead of updated -> Option C
Quick Check:
Use += to update balance, not = [OK]

Quick Trick: Use += to add transactions, not = [OK]

Common Mistakes:

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