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Hardware interview practice

Score legal packet drops without hiding errors

HardReference ModelsPYTHON

Implement a scoreboard for a design allowed to drop 7 through 13 packets in each completed 100-packet outcome window. Duplicate, replayed, invented, and missing-undecided packets remain illegal.

Reviewed example

Work through one case

Input
input IDs 0..99; explicit drops={2,15,28,41,54,67,80,93}; deliver every other ID; then try output ID 101
Expected output
100-outcome window PASS with 8 legal drops; output 101 is rejected as invented

Eight drops lie inside the allowed 7..13 range, every input gets one explicit outcome, and the next invented delivery cannot be hidden by drop tolerance.

What to cover

Requirements

  1. Record every unique input ID as pending before accepting a delivery or drop outcome.
  2. Require a separate deadline or policy layer to declare a packet dropped; absence at the output is not immediately a drop.
  3. Reject output IDs that were never input and IDs already completed by delivery or drop.
  4. Check the drop count only after 100 explicit outcomes, then begin a fresh window.
Continue practicing
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