September 2017 Update

Task/Remove-duplicate-elements/Lua/remove-duplicate-elements-2.lua

@@ -0,0 +1,15 @@
+local items = {1,2,3,4,1,2,3,4,0/0,nil,"bird","cat","dog","dog","bird",0/0}
+
+function rmdup(t)
+  local r,dup,c,NaN = {},{},1,{}
+  for i=1,#t do
+    local e = t[i]
+    local k = e~=e and NaN or e
+    if k~=nil and not dup[k] then
+      c, r[c], dup[k]= c+1, e, true
+    end
+  end
+  return r
+end
+
+print(table.concat(rmdup(items),' '))