benefits from Huawei's written examination(华为笔试题的收获C/C++基础)
1、预编译符号##除了在#include#define这样的预编译指令中用到外还可以起到将后便的标识符扩展为字符串如:#defineprint(x)printf("theno,"#x",is")若在函数中调用了这样一个宏print(123456);则编译后扩展为printf("theno,""123456"",is");2、sizeof、strlensizeof()测试给定变量或类型的‘类型长度’