Software Engineer Interview Experience

Invoice Reconciliation

Stripe’s Invoicing product allows businesses to create and send invoices to their customers. While many invoices can be paid directly, there are cases where standalone payments need to be reconciled with open invoices for a customer. Your task is to write a program that matches incoming payments to their corresponding invoices based on the payment’s memo line. You are given: • A payment string • A list of invoice strings The payment string is a comma-separated string containing: The payment ID (e.g., “payment123”) The payment amount in USD minor units (e.g., $1.00 = 100) The memo line, which always follows the format “Paying off: {INVOICE_ID}” Each invoice string is also comma-separated and contains: The invoice ID The due date of the invoice (e.g., “2024-01-01”) The amount due in USD minor units You need to: • Parse the payment and invoices. • Find the invoice mentioned in the memo line. • Output a formatted string describing the reconciliation. Input Example: payment = "payment5,1000,Paying off: invoiceC" invoices = [ "invoiceA,2024-01-01,100", "invoiceB,2024-02-01,200", "invoiceC,2023-01-30,1000" ] Expected Output: payment5 pays off 1000 for invoiceC due on 2023-01-30