/* **名称:栈的应用——实现四则运算表达式求值 **用途: **(1)中缀表达式转后缀表达式(只支持0-9以内的数) **(2)对后缀表达式进行四则运算 **附属文件:RPN.c RPN.h **Author:yzs **Time:2021.10.02 */ #include "RPN.h" int main() { FILE *ip,*op; ip = fopen("input.txt", "r"); op = fopen("output.txt", "w"); SqStack *stack; stack=(SqStack*)malloc(sizeof(SqStack)); char expreesion[MAXSIZE]; char *expr=expreesion; expr=transform(stack,ip,expreesion); /* for (int i=0;i