How should I practice Partition a Card Deck into Fifteens?

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

Is Partition a Card Deck into Fifteens associated with Meta?

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

Partition a Card Deck into Fifteens

Meta● HardFULLTIMEONSITE INTERVIEW

Learn

Problem statement

Given the visible values of an entire card deck, decide whether every card can be consumed by partitioning the deck into disjoint groups of exactly three cards whose values sum to 15.

Cards are distinct physical cards even when values repeat. Every card must appear in exactly one group.

Function

canPartitionIntoFifteens(cards: int[]) → boolean

Examples

Example 1

cards = [1,5,9,2,6,7]return = true

The deck can be grouped as (1,5,9) and (2,6,7).

Example 2

cards = [1,1,1]return = false

The only triple sums to 3.

Example 3

cards = [5,5,5,5,5,5]return = true

Two identical triples each sum to 15.

Constraints

0 <= cards.length <= 36 and its length is divisible by 3.
1 <= cards[i] <= 9.