How should I practice Linked Merchants Within Two Hops?

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

Is Linked Merchants Within Two Hops associated with Stripe?

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

Problem · Array

Linked Merchants Within Two Hops

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Problem statement

Each merchant record is encoded as merchantId|email|merchantName. Merchant IDs are unique. Two distinct merchants have a direct link when their email values match exactly or their merchant-name values match exactly.

A direct edge has confidence 100 when both fields match and 50 when exactly one field matches. Starting from targetMerchantId, include every other merchant reachable by a path of one or two direct edges. The confidence of a path is the minimum confidence of its edges.

For each reachable merchant, keep the path with the highest confidence. When several paths have that confidence, keep the one with fewer hops. Emit the merchant only once as merchantId|hops|confidence. Sort the final strings by merchant ID in ascending lexicographic order.

Function

linkedMerchantsWithinTwoHops(merchants: String[], targetMerchantId: String) → String[]

Examples

Example 1

merchants = ["a|x@shop.com|North","b|x@shop.com|East","c|y@shop.com|East","d|x@shop.com|North","e|z@shop.com|West"]targetMerchantId = "a"return = ["b|1|50","c|2|50","d|1|100"]

b shares the email with a. c is two hops away through b. d shares both identity fields with a and therefore has confidence 100.

Example 2

merchants = ["a|root@x.com|Root","b|root@x.com|Blue","c|c@x.com|Root","d|root@x.com|Root","e|c@x.com|Blue"]targetMerchantId = "a"return = ["b|1|50","c|1|50","d|1|100","e|2|50"]

e is reachable through both b and c, but it appears once. The direct merchants also remain unique even when additional two-hop paths reach them.

Constraints

1 <= merchants.length <= 2000.
Every record has exactly three nonempty pipe-separated fields.
merchantId, email, and merchantName are case-sensitive printable ASCII strings of length at most 100 and contain no pipe.
targetMerchantId identifies exactly one input record.