Resolve Two Knights-and-Knaves Statements
Company: Sig
Role: Data Scientist
Category: Statistics & Math
Difficulty: easy
Interview Round: Online Assessment
# Resolve Two Knights-and-Knaves Statements
An island has knights, who always tell the truth, and knaves, who always lie. Two people, A and B, make these statements:
- A: “We are different types.”
- B: “A always lies.”
Determine whether each person is a knight or a knave. Justify the result by checking every logically possible type for A.
### What a Strong Answer Covers
- The consequences of assuming A is a knight.
- The consequences of assuming A is a knave.
- Consistency of each speaker's statement with the assigned type.
- A clear reason the rejected case is contradictory.
### Follow-up Questions
- Is B's statement logically equivalent to saying that A is a knave?
- What changes if a third type of person may alternate between truth and lies?
Overview: Resolve a two-person knights-and-knaves puzzle through complete case analysis. The solution shows that assigning A as a knight and B as a knave is consistent, while the alternative forces a knave to make a true statement.
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