该程序实现给定两个整数集合的并集和交集，并且输出。

The program to achieve a given set of two integers and sets and intersection, and the output.

特别地，当D是某正整数集合，Z是整数集时，得出了整数距离图G（Z ，D）的点荫度的几个上界。

In particular, some upper bounds of the vertex arboricity of the integer distance graph G(Z, D) are obtained when D is a set of positive integers and Z the set of all integers.

两个有符号整数相加的结果是一个有符号的整数。

Addition of two signed ints results in a signed int.

集合级安全性用来关联集合与授权用户组。

Collection level security is used to associate collections with sets of authorized users.

我们会忽略负整数。

We're ignoring invalid negative integers.