val a = Operator("/",
  Pair([
    Operator("/", Pair([Variable "prva", Constant 2]))
    ,
    Operator("/", Pair([Constant 2, Constant 3]))
  ]))


val b = Operator("/",
  Pair([
  Operator("/", Pair([

  Operator("/", Pair([Variable "prva", Constant 3])) ,

  Operator("/", Pair([Variable "druga", Constant 6])) ]))

    ,
  Operator("/",   Pair([

  Operator("/", Pair([Variable "tretjea", Constant 3])) ,

  Operator("/", Pair([Variable "cetrta", Constant 1])) ]))
    ]))


val c = Operator("/", Pair([
  Operator("/", Pair([

    Operator("/", Pair([
      Operator("/", Pair([Constant 1, Constant 1]))
        ,
      Operator("/", Pair([Constant 10, Constant 2]))

      ]))
    ,

    Operator("/", Pair([
      Operator("/", Pair([Constant 3, Constant 11]))
        ,
      Operator("/", Pair([Constant 5, Constant 4]))
      ]))
    ]))

  ,

  Operator("/", Pair([

    Operator("/", Pair([
      Operator("/", Pair([Constant 5, Constant 5]))
        ,
      Operator("/", Pair([Constant 6, Constant 6]))
      ]))

    ,
    Operator("/", Pair([
      Operator("/", Pair([Constant 7, Constant 7]))
        ,
      Operator("/", Pair([Constant 8, Constant 8]))
      ]))

    ]))


  ]))


val d = Operator("/", Pair([
  Operator("/", Pair([

    Operator("/", Pair([
      Operator("/", Pair([Variable "prva", Constant 1]))
        ,
      Operator("/", Pair([Constant 10,  Variable "druga"]))

      ]))
    ,

    Operator("/", Pair([
      Operator("/", Pair([Constant 3, Constant 11]))
        ,
      Operator("/", Pair([ Variable "cetrta", Constant 4]))
      ]))
    ]))

  ,

  Operator("/", Pair([

    Operator("/", Pair([
      Operator("/", Pair([Constant 5, Constant 5]))
        ,
      Operator("/", Pair([Constant 6, Variable "sesta"]))
      ]))

    ,
    Operator("/", Pair([
      Operator("/", Pair([Variable "sedma", Constant 7]))
        ,
      Operator("/", Pair([Constant 8, Constant 8]))
      ]))

    ]))


  ]))