Školjka

%V0 Let $P(z)$ and $Q(z)$ be complex-variable polynomials, with degree not less than $1$. Let $$P_k = \{z \in \mathbb C | P(z) = k \}, Q_k = \{ z \in \mathbb C | Q(z) = k \}.$$ Let also $P_0 = Q_0$ and $P_1 = Q_1$. Prove that $P(z) \equiv Q(z).$