mod=2000
ans=1500
n=gets.to_i
a=gets.split.map{|i|i.to_i*mod}.sort+[10**9]
b=gets.split.map{|i|i.to_i/2}

for i in 1..n do
  pq=a.dup
  cnt=0
  
  b.rotate(i).each{|e|
    l=pq.shift
    up=l+e*mod+1
    pq.insert((0..n-1).bsearch{|x|pq[x]>=up},up)
  }
  
  cnt=pq.map{|x|x%mod}.max
  ans=cnt if ans>cnt
end

puts ans