selectUtxos

Select UTXOs using smallest-first algorithm.

Algorithm:

1. Start with empty selection and zero sum

2. For each UTXO (in ascending value order):

• Add UTXO to selection

• Add UTXO value to sum

• If sum >= required amount, stop and return success

3. If reached end without sufficient funds, return failure

Example:

Required: 100
Available UTXOs: [10, 25, 50, 75, 100]

Selection process:
- Add 10 → sum = 10 (< 100, continue)
- Add 25 → sum = 35 (< 100, continue)
- Add 50 → sum = 85 (< 100, continue)
- Add 75 → sum = 160 (>= 100, STOP!)

Result: [10, 25, 50, 75], change = 60

Parameters