不带括号算术式求值另外一个版本 可以自动判断优先级 排除空格等字符影响-Without brackets evaluation arithmetic type another version can automatically determine the priority level to exclude characters such as spaces impact

C的简易计算器代码，支持括号，优先级等等运算但是不支持散件函数等处等函数(Calculator of C but is not repreciable for the function like sin cos tan)