Let C = {wwR| w ∈ {0,1}^*}. Prove that C is not a DCFL. Suppose that when some DPDA P is started in state q with symbol x on the top of its stack, P never pops its stack below x, no matter what input string P reads from that point on. In that case, the contents of P’s stack at that point cannot affect its subsequent behavior, so P’s subsequent behavior can depend only on q and x.