{-# LANGUAGE BangPatterns #-}
import Control.Arrow
import Data.Int
import Data.Foldable
import qualified Data.Vector.Unboxed as VU
import qualified Data.ByteString.Char8 as B

solve :: Int -> VU.Vector Int16 -> Int32
solve n hs = fst dp
 where
  -- dp[i]: minimal cost of moving from 1st to i-th place
  dp :: (Int32, Int32)
  dp = VU.foldl'
    (\(!dp1, !dp2) (!i, !v) -> if i == 0
      then (0, dp1)
      else if i == 1
        then (dp1 + abs (fromIntegral $ v - hs VU.! 0), dp1)
        else
          ( min (dp1 + abs (fromIntegral $ v - hs VU.! (i - 1)))
                (dp2 + abs (fromIntegral $ v - hs VU.! (i - 2)))
          , dp1
          )
    )
    (-1, -1)
    (VU.indexed hs)

main = do
  let readInt :: Integral a => B.ByteString -> Maybe (a, B.ByteString)
      readInt = fmap (first fromIntegral . second B.tail) . B.readInt

  n  <- (\vec -> (vec VU.! 0)) . VU.unfoldrN 1 readInt <$> B.getLine
  hs <- VU.unfoldrN n readInt <$> B.getLine
  print $ solve n hs
