顺序表上基本操作的实现

#include <stdio.h>
#include <stdlib.h>
#define N 100
typedef struct student
{
	char num[4];
	char name[20];
	float  score;
}stu;
typedef struct
{
	stu data[N];
	char *elem;
	int length;

}SqList;

//建表
void creatList(SqList *&L, stu a[], int n)
{
	int i;
	L = (SqList *)malloc(sizeof(SqList));
	for (i = 0; i < n; i++)
		L->data[i] = a[i];
	L->length = n;
}
//初始化表
void initList(SqList *&L)
{
	L = (SqList *)malloc(sizeof(SqList));
	L->length = 0;
}
//插入一个学生信息
void ListInsert(SqList *&L, int i, stu e)
{
	int j;
	if (i<1 || i>L->length)
		printf("Error");
	else
	{
		for (j = L->length - 1; j >= i - 1; j--)
			L->data[j + 1] = L->data[j];
			L->data[i - 1] = e;
			L->length++;
			printf("\nOK");
	}
}
//删除一个学生信息
void ListDelete(SqList *&L, int i, stu e)
{
	int j;
	if ((i < 1) || (i > L->length))
		printf("Error");
	for (j = 1; j <= L->length; j++)
		L->data[j - 1] = L->data[j];
	L->length--;
	printf("\nOK");
}
//修改一个学生的信息
void Listchange(SqList *&L, int i, stu e) {
	if ((i < 1) || (i > L->length))
		printf("Error");
	L->data[i - 1] = e;
	printf("\nOK");
}
//读表
void read(SqList *&L)
{
	int i;
	printf("\n当前的学生信息表如下：\n");
	for (i = 0; i < L->length; i++)
		printf("%s %s %f\n", L->data[i].num, L->data[i].name, L->data[i].score);

}
int main()
{
	int choice, n;
	SqList *L;
	stu A[5] = { {"01","张  三",80},{"02","李  四",90},{"04","王  五",92},{"06","赵  雷",86},{"08","王晓丽",75} };
	stu B;// = { "\0","\0",00 };
	creatList(L, A, 5);
	read(L);
	while (1)
	{
		printf("\n");
		printf("1.插入一个学生的信息\n");
		printf("2.修改一个学生的信息\n");
		printf("3.删除一个学生的信息\n");
		printf("4.退出\n");
		scanf_s("%d", &choice);
		switch (choice)
		{

		case 1:printf("请输入要插入的学生信息:\n");
			scanf_s("%s%s%f",B.num,B.name,B.score);
			printf("请输入要插入的位置:\n");
			scanf_s("%d", &n);
			ListInsert(L, n, B);

			read(L);
			break;
		case 2:printf("请输入要修改的学生位置:\n");
			scanf_s("%d", &n);
			printf("请输入要修改的学生信息:\n");
			scanf_s("%s%s%f", &B.num, &B.name, &B.score);
			Listchange(L, n, B);

			read(L);
			break;
		case 3:printf("请输入要删除的学生位置:\n");
			scanf_s("%d", &n);
			ListDelete(L, n, B);

			read(L);
			break;
		case 4:return 0;

		default:printf("ERROR");
		}
	}

}