全局变量 -全局变量即在函数之外定义的变量 -全局变量保存在静态存储区 注意: -全局变量只能声明和初始化 -全局变量不能进行运算.赋值(非初始化).调用函数 -否则会出现编译错误 -error: expected constructor, destructor, or type conversion before '.' token -initializer element is not constant eg: #include <stdio.h> ; ; int c = a+b;// e…
1.Preprocessor Glue: The ## Operator 预处理连接符:##操作符 Like the # operator, the ## operator can be used in the replacement section of a function-like macro.Additionally, it can be used in the replacement section of an object-like macro. The ## operator co…