【c语言】结构体大小计算的例子

// 结构体大小计算的例子
// 默认对齐数为4

#include <stdio.h>

union tagAAA
{
	struct
	{
		char ucFirst;//1
		short ucSecond;//2
		char ucThird;//1
	}half;
	short kk;//2
}number;

struct tagBBB
{
	char ucFirst;//1
	short ucSecond;//2
	char ucThird;//1
	short ucForth;//2
}half;

struct tagCCC
{
	struct
	{
		char ucFirst;//1
		short ucSecond;//2
		char ucThird;//1
	}half;
	long kk;//4
};

int main()
{
	printf("%d\n", sizeof(union tagAAA));
	printf("%d\n", sizeof(struct tagBBB));
	printf("%d\n", sizeof(struct tagCCC));
	return 0;
}

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