01 / the interview
After solving 32 logic challenges and inverting 1,024 linked lists, Andy finally reached the last interview step.
The meeting room was empty except for a terminal, a whiteboard, and Bob.
Bob did not look up from his coffee.
“Andy, right?”
Andy nodded.
Bob pointed at the terminal.
“Good. One of our generated systems crashed last night. Three processes were running, three access tokens were active, and three resources were being touched. One process crashed while accessing one resource with an invalid token.”
Andy frowned. “So this is debugging?”
Bob smiled.
“No. This is troubleshooting.”
He tapped the whiteboard.
“Find which process crashed. Enter it as process, token, resource.”
parser was not using token-alpha./cache was using token-gamma.crawler was accessing /cache.token-alpha was accessing /logs.token-beta was invalid.renderer was not using token-beta.Alright, let's work through this. The table has two halves: the left three columns are tokens, the right three are resources. Each row is a process.
Mark an ✕ when you can rule something out. Mark a ✓ when you're sure of a match. Start with what the clues tell you directly.
One rule: each process holds exactly one token and accesses exactly one resource. No sharing, no duplicates. So when you confirm a match, you can rule out everything else in that row and column.
Clue 1 says parser was NOT using token-alpha. That's an ✕ in the parser row, token-alpha column.
Clue 3 says crawler was accessing /cache. That's a ✓. And if crawler has /cache, the other two processes don't — mark ✕ for parser×/cache and renderer×/cache. Also mark ✕ for crawler×/logs and crawler×/models since crawler already has its resource.
Clue 6 says renderer was NOT using token-beta. Another ✕.
Now is time for deduction! Clue 2 says the process accessing /cache was using token-gamma. Clue 3 says crawler accesses /cache. So crawler uses token-gamma — mark a ✓ in token-gamma×crawler.
Clue 5 says token-beta was invalid — that's the crash token. Crawler has token-gamma, so crawler didn't crash.
Keep eliminating. When a row or column has only one empty cell left, that's your match. Fill it all in and enter your answer below.
fault
Process crash — invalid access token
scenario
eval-01 / interview exercise
crash time
23:42:44
| parser | crawler | renderer | /cache | /logs | /models | |
|---|---|---|---|---|---|---|
| token-alpha | ||||||
| token-beta | ||||||
| token-gamma | ||||||
| /cache | ||||||
| /logs | ||||||
| /models |
Question: Which process crashed, which token was it using, and which resource was it accessing?