18 lines
427 B
Racket
18 lines
427 B
Racket
#lang racket
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(define (generate n)
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(list->string (shuffle (append* (make-list n '(#\[ #\]))))))
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(define (balanced? str)
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(let loop ([l (string->list str)] [n 0])
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(or (null? l)
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(if (eq? #\[ (car l))
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(loop (cdr l) (add1 n))
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(and (> n 0) (loop (cdr l) (sub1 n)))))))
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(define (try n)
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(define s (generate n))
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(printf "~a => ~a\n" s (if (balanced? s) "OK" "NOT OK")))
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(for ([n 10]) (try n))
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