Amazon | AWS | SDE2 role
May 11, 2026 · 3 reads
Summary
I had a phone screen round with Amazon AWS where I was asked one coding question related to task scheduling with dependencies and cooldown constraints.
Full Experience
Hi,
This was the question asked to me today in AWS phone screen round :
You are given n tasks. Each task has:
- A type (string/character)
- A list of dependencies (other tasks that must finish first)
Rules:
- Each task takes 1 unit of time to execute.
- Tasks of the same type must be separated by a cooldown of k units (i.e., after executing a task of type X at time t, the next task of type X can only run at time ≥ t + k + 1).
- A task is ready only after all its dependencies have completed.
- If no task is ready or all ready tasks are blocked by cooldown, time advances (idle).
Find the minimum time to complete all the tasks.
example :
{t1 -> "A",
t2->"A",
t3->"B",
t4->"A",
t5->"B"}
dependencies : {[t3,t1], [t4, t2]}
cooldown : 2
result : 7
Interview Questions (1)
1.
Task Scheduling with Dependencies and Cooldown
Data Structures & Algorithms·Hard
You are given n tasks. Each task has:
- A type (string/character)
- A list of dependencies (other tasks that must finish first)
Rules:
- Each task takes 1 unit of time to execute.
- Tasks of the same type must be separated by a cooldown of k units (i.e., after executing a task of type X at time t, the next task of type X can only run at time ≥ t + k + 1).
- A task is ready only after all its dependencies have completed.
- If no task is ready or all ready tasks are blocked by cooldown, time advances (idle).
Find the minimum time to complete all the tasks.
Example:
Tasks: {t1 → "A", t2→"A", t3→"B", t4→"A", t5→"B"}
Dependencies: {[t3,t1], [t4, t2]}
Cooldown: 2
Result: 7