Suppose that we say: 

Cons lst = null;
for (int i = 0; i < 3; i++ )
    lst = cons( i, lst );
lst = nreverse(lst);

What is the value of lst?

  • A: (1 2 3)
  • B: (3 2 1)
  • C: (0 1 2 3)
  • D: (0 1 2)
  • E: (2 1 0)

    Answer: D

    cons builds the list backwards compared to the order of item creation. nreverse reverses it, using the same Cons cells ("Read my lips: No new Conses!"), putting the result into forward order.

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