21 lines
482 B
Text
21 lines
482 B
Text
(define balanced-brackets-0
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[] 0 -> true
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[] _ -> false
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[#\[|R] Sum -> (balanced-brackets-0 R (+ Sum 1))
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_ 0 -> false
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[_ |R] Sum -> (balanced-brackets-0 R (- Sum 1)))
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(define balanced-brackets
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"" -> true
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S -> (balanced-brackets-0 (explode (INTERN S)) 0))
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(balanced-brackets "")
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(balanced-brackets "[]")
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(balanced-brackets "[][]")
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(balanced-brackets "[[][]]")
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(balanced-brackets "][")
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(balanced-brackets "][][")
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(balanced-brackets "[]][[]")
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