sameVars :: Monomial -> Monomial -> Bool
sameVars (Monomial _ a) (Monomial _ b) | (sort a) == (sort b) = True
                                         | otherwise = False
sameVars :: Monomial -> Monomial -> Bool
sameVars (Monomial _ a) (Monomial _ b) | (sort a) == (sort b) = True
                                         | otherwise = False
sameVars (Monomial _ a) (Monomial _ b) | (sort a) == (sort b) = True
                                         | otherwise = False