System Design for Splitwise App.

User Class

• userID
• userName
• balance

Methods

• addUser()
• createExpense()
• addPayment()
• calculateBalance()

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Expense Class

• expenseID
• description
• totalAmount
• creatorID
• participants

Methods

• addParticipantToExpense()

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Payment Class

• paymentID
• payerID
• receiverID
• amount