Compute minimal transactions to settle debts
Company: Pinterest
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: Medium
Interview Round: Onsite
You are given a list of transactions (payer, payee, amount) among a set of people. Compute a sequence of transfers that settles all net balances using the minimum number of transactions; return any optimal solution. Amounts are integers; there can be up to 20 distinct people. Describe your algorithm, complexity, and how you would handle multiple optimal answers and large intermediate balances.
Quick Answer: This question evaluates a candidate's algorithm design and combinatorial optimization skills, focusing on reasoning about net balance consolidation, transaction minimization, and complexity analysis.