{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE BangPatterns #-}

import Control.Applicative
import Control.Monad
import Control.Arrow
import Data.List
import Data.Maybe
import Data.Char
import qualified Data.ByteString.Char8 as B
import Text.Printf

readInt = ( readLn :: IO Int )
readInts = map ( read :: String -> Int ) . words <$> getLine

getList = map ( fst . fromJust . B.readInt ) . B.words <$> B.getLine

which a b f = if f then a else b
mp [ a, b ] = ( a, b )

main = do
	getLine
	s <- getLine
	let
		turn_l = map ( which 1 0 . ( == 'E' ) ) s
		turn_r = map ( 1 - ) turn_l
	print $ minimum $ zipWith (+) ( tail $ scanr (+) 0 turn_l ) ( scanl (+) 0 turn_r )