Problem · Hash Table

Stream Latest Log Versions

MediumGoogleONSITE INTERVIEW
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Problem statement

Process a finite sequence of log-stream operations from left to right. Each log is a pair containing an integer timestamp and a message. At most one version of each message is pending at a time.

The problem statement continues
Pro

Examples

Example 1

operations = ["add","add","add","get","get","add","get"]timestamps = [5,8,3,0,0,2,0]messages = ["build","build","deploy","","","build",""]return = ["3|deploy","8|build","2|build"]

The timestamp 8 version replaces build at timestamp 5. The first two results are therefore 3|deploy and 8|build. Once build is returned, adding it at timestamp 2 starts a new lifecycle.

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Reported in 1 Google interview this week

Unlock this recently reported problem

FastPrep Pro gives you full access to interview problems reported within the last week.

  • Full problem statement and constraints
  • 1 more worked example, explained
  • Guided hints and editorial
  • Run your code on real test cases
$9/month

Pro subscription, billed yearly — or $19 month-to-month. Cancel anytime.

Free plan — 2 of 2 free unlocks used this week