$h={}
def f a,b
  $h[a+b.sort]||=(if a[0]
    (0..b.size-1).map{|i|
      c=b.dup
      n,_=c[i]
      if n>=a[0]
        c[i]=[n-a[0],true]
        f(a[1..-1],c)
      else
        nil
      end
    }.compact.min
  else
    b.count{|i,j|j}
  end)
end
gets
a=gets.split.map(&:to_i)
gets
b=gets.split.map{|c|[c.to_i,false]}
p f(a,b)||-1