new files

Task/Balanced-brackets/Racket/balanced-brackets.rkt

@@ -0,0 +1,17 @@
+#lang racket
+
+(define (generate n)
+  (list->string (shuffle (append* (make-list n '(#\[ #\]))))))
+
+(define (balanced? str)
+  (let loop ([l (string->list str)] [n 0])
+    (or (null? l)
+        (if (eq? #\[ (car l))
+          (loop (cdr l) (add1 n))
+          (and (> n 0) (loop (cdr l) (sub1 n)))))))
+
+(define (try n)
+  (define s (generate n))
+  (printf "~a => ~a\n" s (if (balanced? s) "OK" "NOT OK")))
+
+(for ([n 10]) (try n))