Transaction Fee Calculator

Problem Overview

You are given a CSV-formatted string representing a list of payment transactions. Each row contains fields such as: id, reference, amount, currency, date, merchant_id, buyer_country, transaction_type, payment_provider, and status. Example input: Part 1: Parse the CSV string and, for each transaction, calculate the fee based on the payment_provider (and/or payment_type/status).…

• 3 candidate-reported follow-ups — the exact probes interviewers asked, with the trigger for each
• The rest of the problem statement — full requirements, constraints, and edge cases
• Approach and trade-offs — what passing candidates did, and the mistakes that sink people