//联合体的关键字：union
//结构体的关键字：struct
//枚举的关键：enum

struct s
{
	char c;//0
	//1~3 浪费了
	int i;//4~7
};

union un//联合体的声明
{
	char c;
	int i;
};

int main()
{
	printf("%zd\n", sizeof(struct s));//8
	printf("%zd\n", sizeof(union un));//4

	return 0;
}

  

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