haskell, 199 bytes

Result

WA

Duration

1099ms

Code [DL]

import Data.List
import Control.Monad
main = do
 x<-i
 y<-i
 let u=[r x c] in putStr$intercalate "\n"$u++r (y-2) ([c]++r (x-2) ' '++[c])++u
 where
  i=liftM read getLine::IO Int
  c='*'
  r=replicate

stdin

52
72

stdout

****************************************************
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****************************************************

stderr