judgebrackets

代码说明：

  假设一个算术表达式中可以包含三种括号：圆括号“（”和“）”，方括号 “[”和“]”以及花括号“{”和“}”，且这三种括号可按任意的次序嵌套使 用。该算法用于判断给定表达式中所含括号是否配对出现。(Suppose an arithmetic expression can contain three types of brackets: parentheses " (" and " )" , in square brackets " [" and " ]" and braces " {" and " }" , and can use any of these three brackets order nested. The algorithm used to determine a given expression contained in parentheses are paired appear.)