题目

Australian Great Barrier Reef -- a great collection of thousands of smaller coral(珊瑚) reefs, is the world’s largest reef system. It is over 2,600 kilometers long. It goes from the northern tip of Queensland to the state’s southern city of Bundaberg -- was given World Heritage(世界遗产) status in 1981. The UN says it is the “most biodiverse” (物种最为多样性)of all the World Heritage sites, and of “great scientific importance”.The reef is home to many animals: fish, birds, turtles, sharks and even whales. Unfortunately, the reef that all these animals call home is in d设a，b，c∈R且abc≠0，则由代数式a|a|+b|b|+c|c|+abc|abc|的值组成的集合为______．（用列举法表示）