Debtsolver

Track and settle debts between parties with the fewest transactions.

Example

```rust use debtsolver::Ledger; use debtsolver::Transaction; use debtsolver::transaction;

fn main() { let mut ledger = Ledger::new();

// Let's say that:
// Alice paid 20 for Bob's lunch
// Bob paid 20 for Charlie's dinner the next day.
ledger.add_transaction(transaction!("Alice", "Bob", (20, "USD")));
ledger.add_transaction(transaction!("Bob", "Charlie", (20, "USD")));

for payment in ledger.settle() {
    println!("{}", payment)
} 
// Debtsolver will resolve this with one payment:
// Alice owes Charlie 20.00 USD


// Now lets say that:
//   Bob paid for Alice's breakfast (20).
//   Charlie paid for Bob's lunch (50).
//   Alice paid for Charlie's dinner (35).
ledger.add_transaction(transaction!("Alice", "Bob", (20, "USD")));
ledger.add_transaction(transaction!("Bob", "Charlie", (50, "USD")));
ledger.add_transaction(transaction!("Charlie", "Alice", (35, "USD")));


for payment in ledger.settle() {
    println!("{}", payment)
} 
// Debtsolver will resolve this with just two payments:
// Bob owes Alice 15.00 USD
// Bob owes Charlie 15.00 USD

}