new files

Task/Knuth-shuffle/CoffeeScript/knuth-shuffle.coffee

@@ -0,0 +1,21 @@
+knuth_shuffle = (a) ->
+  n = a.length
+  while n > 1
+    r = Math.floor(n * Math.random())
+    n -= 1
+    [a[n], a[r]] = [a[r], a[n]]
+  a
+
+counts =
+  "1,2,3": 0
+  "1,3,2": 0
+  "2,1,3": 0
+  "2,3,1": 0
+  "3,1,2": 0
+  "3,2,1": 0
+
+for i in [1..100000]
+  counts[knuth_shuffle([ 1, 2, 3 ]).join(",")] += 1
+
+for key, val of counts
+  console.log "#{key}: #{val}"