柔性数组

#include <stdio.h>
#include <string.h>
#include <memory>

// 学生结构体
typedef struct ST_STUDENT
{
	int nAge;
	char strName[50];
}ST_STUDENT;

// 班级结构体
typedef struct ST_CLASS
{
	char strClassName[50];
	int nLen;// 存储stStudent的长度（即stStudent的元素个数）
	ST_STUDENT stStudent[0];// 定义柔性数组

}ST_CLASS;


int main(int argc, char* argv[])
{
	int nLen = 3;
	int nSize = sizeof(ST_CLASS) + nLen * sizeof(ST_STUDENT);// 注意这里计算内存的大小方式
	ST_CLASS *pstClass = (ST_CLASS*)malloc(nSize);
	memset(pstClass, 0, nSize);

	strcpy(pstClass->strClassName, "计科一班");
	pstClass->nLen = 3;
	strcpy(pstClass->stStudent[0].strName, "张三");
	pstClass->stStudent[0].nAge = 21;

	strcpy(pstClass->stStudent[1].strName, "李四");
	pstClass->stStudent[1].nAge = 22;
	
	
	strcpy(pstClass->stStudent[2].strName, "王五");
	pstClass->stStudent[2].nAge = 23;


	for (int i = 0 ; i < pstClass->nLen ; ++i)
	{
		printf("name: %s, age: %d\n", pstClass->stStudent[i].strName, pstClass->stStudent[i].nAge);
	}

	return 0;
}