9 lines
218 B
Common Lisp
9 lines
218 B
Common Lisp
(define (rot13 str)
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(join
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(map
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(fn(c)
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(cond
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((<= "A" (upper-case c) "M") (char (+ (char c) 13)))
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((<= "N" (upper-case c) "Z") (char (- (char c) 13)))
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(true c)))
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(explode str))))
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