How should I practice Summarize Server Healthcheck Logs?

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Summarize Server Healthcheck Logs

NVIDIA● EasyNEW GRADPHONE SCREEN

Problem statement

Source note: The report describes a short coding task on structured server healthcheck logs made of keys and values, with follow-ups on duplicate records (operations care about the latest check, while an SLA also counts earlier failures) and on records that break the expected structure. These are practice choices: the exact line format (three key=value fields in any order, single spaces, 1 to 9 digit timestamps compared as numbers, server names of 1 to 10 lowercase letters or digits, PASS or FAIL); treating lines with the same server and timestamp as one check and keeping the first; skipping and counting malformed lines instead of using any part of them; the report lines with each server's newest status and failure count, sorted by server, then the DUPLICATE and INVALID counts; the allowed characters; and the size limits of 2000 lines and 100 characters per line. The judged core task matches the source at about 70%.

You are given server healthcheck logs, one record per line. A well-formed line has exactly three key=value fields separated by single spaces, in any order:

timestamp: 1 to 9 digits. Compare timestamps as numbers, so 007 and 7 are the same time.
server: 1 to 10 characters, all lowercase letters or digits.
status: exactly PASS or FAIL.

Any other line is malformed. For example, a line is malformed if it has a missing, extra, or repeated key, a token without exactly one =, an empty value, a leading, trailing, or double space, or a value that breaks the rules above.

Two well-formed lines with the same server and the same timestamp report the same check. Keep only the first one; each later copy is a duplicate, even if its status differs.

Build a report from the kept checks:

For each server, one line "<server> <status> <failures>". Here <status> is the status of the server's newest check (largest timestamp), which tells operations whether the server is healthy now. <failures> is the number of its kept checks with status FAIL, which an SLA report would count. Sort these lines by server name in lexicographic order.
Then the line "DUPLICATE <d>", where <d> is the number of duplicate lines.
Then the line "INVALID <m>", where <m> is the number of malformed lines.

Return the report lines in this order.

Function

summarizeHealthchecks(logs: String[]) → String[]

Examples

Example 1

logs = ["timestamp=1 server=web1 status=PASS","timestamp=2 server=db1 status=FAIL","timestamp=3 server=web1 status=FAIL","timestamp=4 server=web1 status=PASS","timestamp=5 server=db1 status=PASS"]return = ["db1 PASS 1","web1 PASS 1","DUPLICATE 0","INVALID 0"]

db1 failed at time 2 and passed at time 5, so its newest status is PASS with 1 failure.
web1 passed, failed at time 3, then passed at time 4: newest status PASS, 1 failure.
No line is a duplicate or malformed.

Example 2

logs = ["timestamp=10 server=api status=FAIL","server=api status=PASS timestamp=8","timestamp=10 server=api status=FAIL","timestamp=12 server=api status=PASS","timestamp=10 server=api status=PASS"]return = ["api PASS 1","DUPLICATE 2","INVALID 0"]

The second line lists its fields in a different order, which is allowed.
The third and fifth lines repeat time 10 for api, so they are 2 duplicates and are ignored, even though the fifth one says PASS.
The kept checks are times 10 (FAIL), 8 and 12 (PASS). The newest is time 12, so the status is PASS with 1 failure.

Example 3

logs = ["timestamp=5 server=gpu0 status=PASS","timestamp=6 server=gpu0","timestamp=x server=gpu0 status=PASS","timestamp=7 server=gpu0 status=OK","timestamp=8 server=GPU0 status=FAIL","timestamp=9  server=gpu0 status=FAIL"]return = ["gpu0 PASS 0","DUPLICATE 0","INVALID 5"]

Only the first line is well formed. The others are malformed: one is missing status, one has a non-digit timestamp, one has status OK, one has an uppercase server name, and one has a double space. So gpu0 has newest status PASS with 0 failures, and 5 lines are invalid.

Constraints

0 <= logs.length <= 2000
0 <= logs[i].length <= 100
Each logs[i] contains only letters, digits, spaces, and the characters =, -, _, and :.