How should I practice Render a Comment Hierarchy?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Amazon onsite interview problems in FastPrep.

Is Render a Comment Hierarchy associated with Amazon?

FastPrep tags this as a Amazon onsite interview coding practice problem when the problem catalog has that company and stage context.

Problem · Array

Render a Comment Hierarchy

● Medium

AmazonNEW GRADONSITE INTERVIEW

See Amazon hiring insights

Problem statement

You are given three parallel arrays describing a flat collection of comments:

ids[i] is the unique ID of comment i.
parentIds[i] is -1 when comment i is a root; otherwise it is the ID of that comment's parent.
texts[i] is the comment text.

The parent relationships form a valid acyclic forest and may have arbitrary depth. A parent may appear before or after its children in the input.

The problem statement continues

Pro

Examples

Example 1

ids = [10,20,30,40,50]parentIds = [-1,10,10,20,-1]texts = ["Root A","Reply A1","Reply A2","Deep reply","Root B"]return = ["Root A","  Reply A1","    Deep reply","  Reply A2","Root B"]

The first root is followed by its children in input order. The child of Reply A1 has depth two, so it receives four leading spaces. The second root is rendered last.

FastPrep Pro

Reported in 1 Amazon interview this week

Unlock this recently reported problem

FastPrep Pro gives you full access to interview problems reported within the last week.

Full problem statement and constraints
2 more worked examples, explained
Guided hints and editorial
Run your code on real test cases

$9/month

Pro subscription, billed yearly — or $19 month-to-month. Cancel anytime.

Free plan — 2 of 2 free unlocks used this week