Design Algorithm to Minimize Payments in Expense-Sharing App

Scenario

Expense-sharing app needs to settle debts among friends after a trip.

Question

Given a list of transactions (payer, payee, amount), design an algorithm that produces the minimum set of payments required to settle every person’s balance.

Hints

Compute each person’s net balance, then greedily match positives with negatives using a heap or two-pointer sweep.