taking list and strings as a input

The 'sort' function is probably your best starting point...

    Cadence SKILL Language Reference -- sort

The 'sort' function is probably your best starting point...

    Cadence SKILL Language Reference -- sort

How to take list as a input from user? 

Thank you for your quick reply

The most common way is to use a Form with a string field, in which each item is space or comma separated.  For example:

procedure( GetStringAsList()
  let((stringField topLayout formId)
    stringField = hiCreateStringField(
      ?name 'stringField
      ?prompt "Enter Strings:"
      ?value ""
    )
    topLayout = hiCreateFormLayout('topLayout
      ?items list(stringField)
    )
    formId = hiCreateLayoutForm('TheForm "Input String(s)" topLayout
      ?callback 'GetStringAsListCB
      ?buttonLayout 'OKCancelDefApply
      ?unmapAfterCB t
      ?dialogStyle 'modal
    )
    hiDisplayForm(formId)
    ;; Return the list
    formId->sortedList
  ); let
); procedure


procedure( GetStringAsListCB(formId)
  let((stringVal sortedList)
    stringVal = formId->stringField->value
    if(blankstrp(stringVal) then
      hiHighlightField(formId 'stringField 'error)
      hiSetCallbackStatus(formId nil)
    else
      sortedList = sort(parseString(stringVal " ,:") 'alphalessp)
      info("Sorted List = %L\n" sortedList)
      hiSetCallbackStatus(formId t)
    ); if
    formId->sortedList = sortedList
  ); let
); procedure


sortedList = GetStringAsList()