2016 Update

Task/Sorting-algorithms-Merge-sort/Lua/sorting-algorithms-merge-sort.lua

@@ -0,0 +1,22 @@
+function getLower(a,b)
+  local i,j=1,1
+  return function()
+    if not b[j] or a[i] and a[i]<b[j] then
+      i=i+1; return a[i-1]
+    else
+      j=j+1; return b[j-1]
+    end
+  end
+end
+
+function merge(a,b)
+  local res={}
+  for v in getLower(a,b) do res[#res+1]=v end
+  return res
+end
+
+function mergesort(list)
+  if #list<=1 then return list end
+  local s=math.floor(#list/2)
+  return merge(mergesort{unpack(list,1,s)}, mergesort{unpack(list,s+1)})
+end