def sortint(f,items)
    items.map{|item|
      [f.call(item).scan(/\d+|[^\d]/).map{|e|  # split string on numeral and other symbols
         if e.to_i.to_s == e  # is_int?
           256+e.to_i         # up char code
         else
           e[0]               # char code
         end
      }, item]
    }.sort{|a,b|
      n = [a[0].count,b[0].count].min-1  # minimum length of two strings
      r = a[0][0..n] <=> b[0][0..n]
      r == 0 ? a[0].count <=> b[0].count : r
    }.map{|_,e| e}
  end