import Control.Applicative
import Control.Monad
import Data.Maybe
import Data.Graph
import qualified Data.ByteString.Char8 as B
 
hypot2 x y = x*x+y*y

solve n ls = bsearch 0 200000000
  where
    dst = [([(i,j),(j,i)],hypot2 (xi-xj) (yi-yj))|(i,[xi,yi])<-zip [0..] ls,(j,[xj,yj])<-zip [0..] ls,i<j]
    bsearch l r
      | l>=r      = l*10
      | check     = bsearch l c
      | otherwise = bsearch (c+1) r
        where
          c       = (l+r)`div`2
          check   = path gr 0 (n-1)
          gr      = buildG (0,n-1) $ concatMap fst $ filter ((100*c*c>=).snd) dst

main = do
  n  <- fst . fromJust . B.readInt <$> B.getLine
  ls <- replicateM n $ map (fst . fromJust . B.readInt) . B.words <$> B.getLine
  print $ solve n ls