完全通过C语言编写的一个“四则混合运算”功能的小程序，原本是老师布置给我们的‘用于小学生培养计算’能力开发的程序。 包含加法、减法、乘除法、混合运算、历史记录、参数设置等功能。-Function of small programs entirely through a C language " four mixed computing" was originally a teacher assigned to our ' for primary school cult