{-# LANGUAGE ScopedTypeVariables #-}
module Main where
import Data.List
import Control.Monad

readLine :: Read a => IO [a]
readLine = map read . words <$> getLine

main :: IO ()
main = do
    [a1, a2, a3, a4] :: [Int] <- readLine
    putStrLn $ if (a1 < a2 && a3 > a4) then "YES" else "NO"