anchor.diff:      let! l1 = Console.readLine
       let! l2 = Console.readLine
       let! l3 = Console.readLine
  -    do! Console.printf "You entered: %A" [l1; l2; l3]
  +    do! Console.printfn "You entered: %A" [l1; l2; l3]
   } |> IO.run
   
   (**
  
positive.code: 
  let fileIO = io {
      let! lines = File.readLines fName // sequence of io actions which each read a line from a file
      let! floatLines = IO.traverseM (IO.map float) lines // parse each line, collecting the results
      do! IO.traverseM_ (Console.printfn "%f") floatLines // print each float to the console
  }
  
  try
  
negative.code: 
  *)
  
  let exmpl2 = io {return! Console.readLine}
  printfn "%s" (IO.run exmpl2)
  printfn "%s" (IO.run exmpl2)
  
  (**
  
  