import Data.List

main = do
 n <- readLn
 as <- map read . words <$> getLine
 print (jenga n as)

jenga n as = n - masc as
 where
  masc = maximum . map asc . tails
  asc = pred . length . foldl (\(a:acc) x -> if a<x then x:a:acc else a:acc) [0]