September 2017 Update

Task/Sorting-algorithms-Cocktail-sort/OoRexx/sorting-algorithms-cocktail-sort.rexx

@@ -0,0 +1,51 @@
+/* Rexx */
+
+placesList = .array~of( -
+    "UK  London",     "US  New York"   , "US  Boston",     "US  Washington" -
+  , "UK  Washington", "US  Birmingham" , "UK  Birmingham", "UK  Boston"     -
+)
+
+sortedList = cocktailSort(placesList~allItems())
+
+lists = .array~of(placesList, sortedList)
+loop ln = 1 to lists~items()
+  cl = lists[ln]
+  loop ct = 1 to cl~items()
+    say cl[ct]
+    end ct
+    say
+  end ln
+
+return
+exit
+
+::routine cocktailSort
+  use arg A
+
+  Alength = A~items()
+  swapped = .false
+  loop label swaps until \swapped
+    swapped = .false
+    loop i_ = 1 to Alength - 1
+      if A[i_] > A[i_ + 1] then do
+        swap      = A[i_ + 1]
+        A[i_ + 1] = A[i_]
+        A[i_]     = swap
+        swapped = .true
+        end
+      end i_
+    if \swapped then do
+      leave swaps
+      end
+    swapped = .false
+    loop i_ = Alength - 1 to 1 by -1
+      if A[i_] > A[i_ + 1] then do
+        swap      = A[i_ + 1]
+        A[i_ + 1] = A[i_]
+        A[i_]     = swap
+        swapped = .true
+        end
+      end i_
+    end swaps
+
+  return A