Blog Post Title: The Future of Search: Reddit’s Plan to Merge Traditional and AI Search
During a board meeting at Reddit, a group of 10 members – 5 developers and 5 executives – are discussing their plans for merging traditional search methods with artificial intelligence.
The following facts about the discussion are known:
1. Each executive can only speak once.
2. The development team has two representatives who have spoken consecutively in the meeting.
3. The first executive to speak, was not a developer but spoke before the last developer.
4. No two developers have spoken at the same time.
5. The CEO is neither the first nor the last to speak.
6. The COO, who didn’t speak immediately after or before any of the executives, spoke directly after the lead developer.
7. Neither of the lead developers’ speeches were immediately followed by the CEO’s.
8. One executive and one developer spoke immediately after each other in a single speech.
9. Each team member has spoken exactly once except for one person who spoke twice – but not consecutively.
Question: What is the order of speakers?
Start with the fourth clue, which says that no two developers have spoken at the same time. This means that any sequence starting with a developer cannot end in another developer speaking again (since this would violate the first clue).
This leads us to conclude from clues 5 and 9 that the CEO spoke last and one of the executives started the meeting by speaking before him.
Since we know from clue 7 that neither of the lead developers’ speeches were immediately followed by the CEO’s, it means the CEO’s speech was not the second in line either (because then the first developer would have had to follow the CEO which violates the first clue).
From this information and the fact that no two executives spoke consecutively (clue 1), we can deduce that the second speaker is a non-executive. We also know from clues 6 and 8, that the COO and the second developer each spoke immediately before or after another developer who didn’t follow a CEO’s speech – so they could not be the first two speakers.
Now, since there are only 4 developers left to choose from (after considering step 2), by elimination we can say that one of them must be the third speaker.
Then, using clues 6 and 8 once more, it becomes clear that the lead developer immediately followed by the COO was not the fourth one either because they didn’t have a chance for an immediate conversation with any other executive or developer (clue 2), so the developer is the fifth speaker.
With only one non-executive left to choose from (who can’t be the CEO, because he speaks after the first developer who’s a representative of the development team (clue 3)) and the fact that we know the developers are not allowed to immediately follow each other (step 2), the non-executive must be the sixth speaker.
Since no two developers have spoken at the same time (step 1) and the fourth one was also a developer, the seventh member is the executive, then the eighth person has to be another developer. The ninth and tenth members are the remaining executives.
Answer: 1st – COO, 2nd – Developer, 3rd – Developer, 4th – Developer, 5th – Developer, 6th – Non-executive, 7th – Executive, 8th – Developer, 9th – Executive, 10th – Executive
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