ex4_11_1.cpp

纯粹是学习专用～

# include <iostream.h>
void fun2();				//外部函数声明，等价于extern void fun2();
int n;						//全局变量定义
void main(){
n=1;
fun2();					//fun2()定义在文件Ex4_14_2.cpp中
cout<<"n="<<n<<endl;
}