import Control.Applicative
import Data.List
import Data.Array

repeated_combination ns n = comb n [(ns,[])]
  where
    comb 0 xs = [a|(_,a)<-xs]
    comb c xs = comb (c-1) $ concatMap f xs
    f (xs,ys) = [(as,ys++[a])|as@(a:_)<-tails xs]

main = do
  n <- (80-).read <$> getLine
  [a,b,c] <- map ((/100).read) . words <$> getLine
  let pa n m
        | m==0 || m==n+1 = 1
        | n==1 && m==1   = a
        | m==1 || m==n   = b
        | otherwise      = c
      sub nn m [i,j] = foldl (*) ((dp!(nn,(j-i+1)))*(pa m (i-1))*(pa m (j+1))) $ map ((1-).(pa m)) [i..j]
      calc 0  m = fromIntegral m
      calc nn m = foldl1 (+) $ map (sub (nn-1) m) $ repeated_combination [1..m] 2
      dp = array ((0,0),(n,14)) [((i,j),calc i j)|i<-[0..n],j<-[0..14]]
    in print $ (dp!(n,14))*2