How should I practice Order and Batch Open-Close Lifecycle?

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Problem · Array

Order and Batch Open-Close Lifecycle

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Hudson River TradingFULLTIMEPHONE SCREEN

Problem statement

Open and close events are stored separately. Every event has a positive timestamp, an order ID, and a batch ID.

Given the parallel arrays for both event files plus queryType and queryId, return [start, end] for the requested lifecycle:

For an ORDER query, start is that order's open timestamp. end is its close timestamp, or 0 if it has no close event.
For a BATCH query, start is the earliest open timestamp among its orders. If any order in that batch has no close event, end is 0; otherwise, end is the latest close timestamp among those orders.

The input is well formed: every order opens exactly once, closes at most once, and keeps the same batch ID in both files.

Function

getLifecycleWindow(openTimestamps: long[], openOrderIds: String[], openBatchIds: String[], closeTimestamps: long[], closeOrderIds: String[], closeBatchIds: String[], queryType: String, queryId: String) → long[]

Examples

Example 1

openTimestamps = [10,12,15]openOrderIds = ["o1","o2","o3"]openBatchIds = ["b1","b1","b2"]closeTimestamps = [20,25]closeOrderIds = ["o1","o3"]closeBatchIds = ["b1","b2"]queryType = "BATCH"queryId = "b1"return = [10,0]

Batch b1 starts when o1 opens at 10. Order o2 remains open, so the batch end is 0.

Example 2

openTimestamps = [10,12,15]openOrderIds = ["o1","o2","o3"]openBatchIds = ["b1","b1","b2"]closeTimestamps = [20,25]closeOrderIds = ["o1","o3"]closeBatchIds = ["b1","b2"]queryType = "ORDER"queryId = "o1"return = [10,20]

Order o1 opens at 10 and closes at 20.

Example 3

openTimestamps = [5,7,9]openOrderIds = ["a","b","c"]openBatchIds = ["x","x","y"]closeTimestamps = [11,20,15]closeOrderIds = ["a","b","c"]closeBatchIds = ["x","x","y"]queryType = "BATCH"queryId = "x"return = [5,20]

Batch x starts at the earlier open time 5. Both orders close, and the later close is 20.

Constraints

The three open arrays have equal positive length; the three close arrays have equal length.
All timestamps are positive 64-bit integers, and each close timestamp is at least its order's open timestamp.
Every order ID appears exactly once in the open arrays and at most once in the close arrays.
A close event uses the same batch ID as its order's open event.
queryType is ORDER or BATCH, and queryId identifies an existing order or batch of that type.