资 源 简 介
实现基于二叉树表示的算术表达式Expression的操作。
（3） 程序执行的命令为：
1）输入表达式； 2）输出前缀表达式； 3）输出中缀表达式；4）常量合并后表达式；5）赋值后的表达式；6）表达式的复合。
-Binary tree based on the arithmetic expression Expression express operation. (3) procedures for the implementation of the command as follows: 1) input expression 2) expression of the output prefix 3) the output is made up of expressions 4) constant expression after the merger 5) after the assignment expression 6) expression type of composite.
