How should I practice Determine Whether Two Chickens Are Blood Relatives?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Google phone screen problems in FastPrep.

Is Determine Whether Two Chickens Are Blood Relatives associated with Google?

FastPrep tags this as a Google phone screen coding practice problem when the problem catalog has that company and stage context.

Determine Whether Two Chickens Are Blood Relatives

Google● MediumNEW GRADPHONE SCREEN

Learn

Problem statement

A chicken family is represented by direct parent lists. parents[i] contains every direct parent of chicken i. Parent edges form a directed acyclic graph.

Two chickens are blood relatives when their ancestor sets intersect. A chicken is included in its own ancestor set, so an ancestor and descendant are relatives. Merely sharing a child does not make two co-parents blood relatives.

Return whether first and second are blood relatives.

Function

areBloodRelatives(parents: int[][], first: int, second: int) → boolean

Examples

Example 1

parents = [[],[],[0,1],[0,1]]first = 2second = 3return = true

The two chickens share parents 0 and 1.

Example 2

parents = [[],[],[0,1]]first = 0second = 1return = false

The two co-parents share a child but no ancestor.

Example 3

parents = [[],[0],[1]]first = 0second = 2return = true

Chicken 0 is an ancestor of chicken 2.

Constraints

1 <= parents.length <= 200000.
Every listed parent is a valid node index.
The total number of parent edges is at most 300000.
The parent graph is acyclic.
first and second are valid indices.