问题描述：假设一个算术表达式中可包含三种括号：圆括号，方括号和花括号且这三种括号可按任意次序嵌套使用。试利用栈的运算，编写判别给定表达式中所含括号是否正确配对出现的算法。-Problem Descr iption: Suppose an arithmetic expression can contain three types of brackets: parentheses, square brackets and curly braces and brackets can be any of these three nested use of the order. Test the use of the computing stack, the preparation of a given discriminant regular expressions contained in brackets appear correctly matching algorithms.