{"id":"set-early-return-first-duplicate","text":"The first-letter-to-appear-twice solution returns on the first duplicate encountered during left-to-right iteration, guaranteeing the result is the letter whose second occurrence index is minimal.","truth_value":"IN","source":"entries/2026/06/06/first-letter-to-appear-twice-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"set-early-return-first-duplicate","truth_value":"IN","reason":"premise"}]}}