tasks a-s

Task/Power-set/Groovy/power-set-1.groovy

@@ -0,0 +1,14 @@
+def comb
+comb = { m, List list ->
+    def n = list.size()
+    m == 0 ?
+        [[]] :
+        (0..(n-m)).inject([]) { newlist, k ->
+            def sublist = (k+1 == n) ? [] : list[(k+1)..<n]
+            newlist += comb(m-1, sublist).collect { [list[k]] + it }
+        }
+}
+
+def powerSet = { set ->
+    (0..(set.size())).inject([]){ list, i ->  list + comb(i,set as List)}.collect { it as LinkedHashSet } as LinkedHashSet
+}

Task/Power-set/Groovy/power-set-2.groovy

@@ -0,0 +1,3 @@
+def vocalists = [ "C", "S", "N", "Y" ] as LinkedHashSet
+println "${vocalists}"
+println powerSet(vocalists)