Is there a way to retrieve all the salesforce id in an Account hierarchy

I wanted a utility class which will give me a list of all salesforce id's in an Account Hierarchy.

I have an hierarchy of something like below and the hierarchy can span upto many levels in Account.

Capital World Investors (DEMO) – Ultimate PArent

Capital Research Global Investors (DEMO) – Parent

Fidelity Management & Research (DEMO) – Child

Capital Research Market  Investors (DEMO) – Parent

Fidelity Management & Research & Analytics (DEMO) – Child

Any guidance around this is apprecaited

Thanks