MacFormat 1996 July/macformat-039.iso/DATABASE/SHARED.DIR/01029_bsearch script.ls

Text File | 1996-03-14 | 615 b | 26 lines

on Bsearch str, txt
  set txt to the number of cast txt
  set start to 1
  set end to the number of lines in field txt
  set middle to (start + end) / 2
  repeat while str <> item 1 of line middle of field txt
    if str = item 1 of line end of field txt then
      return end
    end if
    if start = middle then
      return 0
    end if
    if str < item 1 of line middle of field txt then
      set end to middle
    else
      set start to middle
    end if
    set middle to (start + end) / 2
  end repeat
  if str = item 1 of line middle of field txt then
    return middle
  else
    return 0
  end if
end