Create a new class named Lab2Class with the following public operations.

创建名为Lab2Class的新类，包含以下共有方法。

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Note that the service specification may only provide public operations, and each operation should only consume at most one message and produce at most one message.

注意服务的规约说明只能提供公开的操作，而且每个操作应当只能消耗至多一条消息、产生至多一条消息。

youdao

Note that the service specification may only provide public operations, and each operation should only consume at most one message and produce at most one message.

注意服务的规约说明只能提供公开的操作，而且每个操作应当只能消耗至多一条消息、产生至多一条消息。

youdao