typedef用法

——为数据类型起一个别名

——为了更加简洁和精炼

#include<stdio.h>
/*
typedef用法 
*/
typedef int Cmy;//为int 取一个别名 即Cmy等价于int 
typedef struct Student
{
	int sid;
	char name[100];
	char sex;
}St;//为struct Student 取一个别名St

typedef struct Student2
{
	int sid;
	char name[100];
	char sex;
}* PST,ST;
/*
PST等价于struct Student2 *   
ST等价于struct Student2 
*/
int main()
{
	int i = 10;
	Cmy j = 10;
	printf("%d-%d\n",i,j);
	struct Student st1;//等价于St st1 
	struct Student * pst = &st1; // 等价于St * pst 
	
	St st2;
	st2.sid = 1000;
	printf("%d\n",st2.sid);
	
	struct Student2 st3;
	PST ps = &st3;
	ps->sid = 99;
	printf("%d\n",st3.sid);
	
	ST st4;//struct Student2 st4
	PST pstu = &st4;//struct Student2 * pstu = &st4
	pstu->sid = 100;
	printf("%d\n",st4.sid);
	return 0;
	
	
}