Location:
![](/images/right.gif)
Search - postfix.t
Search list
Description: 邮件系统是Linux网络应用的重要组成,一个完整的邮件系统包括三个部分:底层操作系统(Linux Operation),邮件传送代理(Mail Transport Agent,MTA),邮件分发代理(Mail Delivery Agent,MDA),邮件用户代理(Mail User Agent,MUA)。
Postfix是一个非常优秀的MTA,她素以高效、安全的特点而著称。Postfix是作者在UNIX上所见过的MTA中在反垃圾邮件(Anti- Spam或Anti-UCE)方面做得最好的一个,甚至有很多公司在Postfix代码的基础上进行二次开发而推出反垃圾邮件网关产品。MTA的反垃圾邮件功能,实际上就是在MTA处理过程中对会话进行过滤。这个过滤不但过滤了发往自身的垃圾邮件,而且还防止了自身被恶意利用发送垃圾邮件。Postfix 实现了目前所有主要的MTA过滤技术。postfix是Wietse Venema在IBM的GPL协议之下开发的MTA(邮件传输代理)软件。和Sendmail相比Postfix更快、更容易管理、更灵活、更安全。
Platform: |
Size: 2782208 |
Author: lu shengxuan |
Hits:
Description: 把中缀表达式转化为后缀表达式……
第一行为T,表示有T组数据;
以下T行每行包含一个字符串,是中缀表达式。
对于每组测试数据数据后缀表达式。-Infix expression to postfix expression into the first act ... ... T, says there are T sets of data the following T lines each line contains a string, is the infix expression. For each test data suffix expressions.
Platform: |
Size: 1024 |
Author: yu |
Hits:
Description: 1、给出文法如下:
G[E]
E->T|E+T
T->F|T*F
F->i(E)
对应的转化为逆波兰式的语义动作如下:
E-> E(1)op E(2) {E.CODE:= E(1).CODE||E(2).CODE||op}
E->(E(1)) { E.CODE := E(1).CODE}
E->id { E.CODE := id}
2、利用实验5中的算符优先分析算法,结合上面给出的语义动作实现逆波兰式的构造;
3、利用栈,计算生成的逆波兰式,步骤如下:
1)中缀表达式,从文本文件读入,每一行存放一个表达式,为了降低难度,表达式采用常数表达式;
2)利用结合语法制导翻译的算符优先分析,构造逆波兰式;
3)利用栈计算出后缀式的结果,并输出;-1 gives grammar as follows: E [E] E-> T | E+ T T-> F | T* F F-> i (E) the corresponding inverse Polish into semantic action as follows:
E-> E (1) op E (2) {E.CODE: = E (1) .CODE || E (2) .CODE || op}
E-> (E (1)) {E.CODE: = E (1) .CODE}
E-> id {E.CODE: = id}
2, the use of experimental 5 operator priority analysis algorithms, combined with semantic actions given above structure to achieve reverse Polish notation
3, the use of the stack, calculates the resulting Reverse Polish Notation, as follows:
1) infix expression, read a text file, each line deposited an expression, in order to reduce the difficulty of using a constant expression expression
2) the use of binding syntax directed translation of operator priority analysis, structural inverse Polish
3) Using the calculated postfix stack of results and outputs
Platform: |
Size: 1024 |
Author: 忆昔 |
Hits: