Amazon Intern VO (Offer!): N-ary Trees + Course Schedule Variant + Full Timeline

Overview

• Role: SDE Intern
• Rounds: two — one with an engineer, one with a manager
• Result: offer 🎉

Behavioral

• Tell me about a time you supported a peer.
• Tell me about a challenging experience.
• The manager asked about my experience with AI-assisted coding.

None of these were hard; I reused stories I had prepared. Since I had used AWS EC2 during a previous internship, the interviewer asked a small follow-up about the implementation.

Coding

1. N-ary tree: count the subnodes of a given node.
2. N-ary tree: find the greatest depth.
3. LC 210 variant: return only the dependency order needed for a given course, and handle cycles.

Approach for Q3: run DFS from the target course and output dependencies in post-order. Keep an extra set of nodes on the current DFS call stack — reaching a node that is already on the stack means there is a cycle, so stop immediately.

def course_order(target, prereqs):
    """prereqs: {course: [courses it depends on]}; returns [] if there is a cycle"""
    order, done, on_stack = [], set(), set()

    def dfs(c):
        if c in on_stack:
            return False  # cycle detected
        if c in done:
            return True
        on_stack.add(c)
        for p in prereqs.get(c, []):
            if not dfs(p):
                return False
        on_stack.remove(c)
        done.add(c)
        order.append(c)
        return True

    return order if dfs(target) else []

Timeline

Date	Progress
2/28	Applied
3/4	OA invite
3/8	Finished OA
3/9, 3/17	Two "still in process" emails
3/30	VO scheduled
4/10	Two VO rounds (engineer + manager)
4/14	Offer 🎉