以字符序列的形式从终端输入语法正确的、不含变量的整数表达式，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符栈、操作数栈、操作数栈和主要操作的变化过程。-In the form of a sequence of characters entered from the terminal grammatically correct, non-integer variable expressions using the operators given priority to relations and the realization of the arithmetic expression is the four mixed-evaluated and demonstrated in the evaluation process operator stack, operand stack, operand stack and the main operation of the process of change.