Robot Puzzle

Suppose A were a trick-bot. Then A’s statement, "At least one of us is a trick-bot" would have to be false—but this would be a contradiction if A were a trick-bot. Therefore, A is a truth-bot.

Since A is a truth-bot, A’s statement is true: at least one robot must be a trick-bot. It isn’t A, so B is the trick-bot.

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