module Main where

import Control.Applicative
import Control.Monad
import Data.List

main :: IO ()
main = do
    [n, m] <- fmap read . words <$> getLine :: IO [Int]
    let p = fromIntegral $ 100 * (n - m) + 1900 * m
    let s = 0.5 ^ m
    let t = 1.0 - s
    let f k = (p * k) * s * (t ^ (floor $ k - 1.0))
    let ans = sum $ takeWhile (>= 0.000001) $ fmap f [1..]
    print $ ceiling ans