编译原理中算符优先表的生成，其中包含了每步骤的显示，进栈和出栈的过程都能完整的显示出来，仅供大家学习借鉴-compiler Principle operator of the priority list generation, which contains every step, into stacks and stack up the integrity of the process can show up only to learn from you

现在要求以字符序列的形式从终端输入语法正确的、不含变量的表达式，利用给定的算符优先关系，实现对算术四则混合运算表达式的求值，并演示在求值过程中运算栈、操作数栈、输入字符和主要操作的变化过程-Now in the form required character sequences from input terminal of the correct grammar, do not contain variables by the operator is given priority to, the

1、编写函数，实现顺序栈的各种基本操作（可从上一实验中直接获取）； 2、编写函数，实现运算符的优先级处理； 3、编写函数，实现算术表达式的计算。 -1, write a function, the stack order to achieve a variety of basic operations (directly obtained from previous experiments) 2, write a function to achieve priority handl