. simp
case inl
R : Type u_1
inst✝¹ : CommSemiring R
inst✝ : PerfectRing R
h✝ : ringChar R = 0
⊢ id 0 = 0

case inr
R : Type u_1
inst✝¹ : CommSemiring R
inst✝ : PerfectRing R
h✝ : ¬ringChar R = 0
⊢ Function.surjInv (_ : Function.Surjective fun x => x ^ ringChar R) 0 = 0
case inr
R : Type u_1
inst✝¹ : CommSemiring R
inst✝ : PerfectRing R
h✝ : ¬ringChar R = 0
⊢ Function.surjInv (_ : Function.Surjective fun x => x ^ ringChar R) 0 = 0