Graph Valid Tree
mediumblind-75dsagraphsunion-find
Asked at
Amazon, Google, LinkedIn, Meta, Microsoft
Problem statement
Implement validTree for the classic Graph Valid Tree problem.
This Blind 75 version is framed for frontend interviews: write clean JavaScript, name the invariant out loud, and handle edge cases without over-engineering.
What this tests
- Pattern:
components and edge count. - Ability to explain time and space complexity clearly.
- Careful handling of empty inputs, duplicates, and boundary cases.
- Production-style JavaScript readability, not just competitive-programming shortcuts.
Requirements & constraints
- Use JavaScript without external libraries.
- Prefer the standard optimal interview approach for this pattern.
- Return deterministic output when multiple valid outputs exist where the prompt implies ordering.
Examples
Example 1
Input: Use the canonical Blind 75 sample for this problem.
Output: Return the value required by the problem statement.
How to approach Graph Valid Tree
The strategy an interviewer expects you to reach for.
Senior Frontend Approach Start by identifying the pattern: components and edge count. Then define the invariant the loop or recursion maintains before writing code.
Premium
The full solution is part of HelloFrontend Pro
The question above is free to read in full. Upgrade to unlock the interactive workspace and the senior-level walkthrough that go with it.
- Runnable editor with the hidden test suite
- Progressive hints that unlock as you get stuck
- Senior-level reference solution with a line-by-line walkthrough
Already a member? Log in to open the workspace.