Sorting algorithms/Counting sort: Difference between revisions

Content added Content deleted

Inline

@@ Line 1,290: / Line 1,290: @@
 (define (counting-sort xs min max)
   (define ns (make-vector (+ max (- min) 1) 0))
-  (for ([x xs]) (vector-set! ns x (+ (vector-ref ns x) 1)))
+  (for ([x xs])
+    (vector-set! ns (- x min) (+ (vector-ref ns (- x min)) 1)))
   (define ys (vector-copy xs))
-  (for/fold ([i 0]) ([n ns] [x (in-naturals min)])
+  (for/fold ([i 0]) ([n ns] [x (in-naturals)])
     (for ([j (in-range i (+ i n ))])
-      (vector-set! ys j x))
+      (vector-set! ys j (+ x min)))
     (+ i n))
   ys)
-(counting-sort #(0 9 3 8 1 1 1 2 3 7 4) 0 10)
+(counting-sort #(0 9 3 8 1 -1 1 2 3 7 4) -1 10)
 </lang>
 Output:
 <lang racket>
-'#(0 1 1 1 2 3 3 4 7 8 9)
+'#(-1 0 1 1 2 3 3 4 7 8 9)
 </lang>