n=gets.to_i
bs=11
bmask=(1<< bs)-1

pq_base=[nil]
gets.split.each.with_index(1){|j,i|
  a=j.to_i<< bs
  i/=2 while i>1 && a<pq_base[i]=pq_base[i/2]
  pq_base[i]=a
}
pq_base<<1e9

el=gets.split.map{|i|(i.to_i/2<< bs)+1}
counts = []
pids = {}
max_procs = 4
(1..n).each{|i|
  if pids.size >= max_procs
    pid = Process.wait
    counts << pids[pid].gets.to_i
    pids[pid].close
    pids.delete(pid)
  end
  read, write = IO.pipe
  pid = fork{
    read.close
    pq=pq_base
    el.rotate(i).each{|e|
      a=pq[n]
      d=pq[i=1]+e
      while (c=i*2)<n
        c+=1 if pq[c]>pq[c+1]
        break if a<=pq[i]=pq[c]
        i=c
      end
      pq[i]=a
      i=n
      i/=2 while i>1 && d<pq[i]=pq[i/2]
      pq[i]=d
    }
    write.puts(pq[1..-2].map{|x|x&bmask}.max)
    write.close
  }
  if pids.key?(pid)
    counts << pids[pid].gets.to_i
    pids[pid].close
  else
    pids[pid] = read
  end
}
Process.waitall.each do |pst|
  counts << pids[pst[0]].gets.to_i
end
puts counts.min