sics/sys.cpp

#include<sys.h>
void studentinit(student t)
{
	t.num = 0;
	t.math = 0;
	t.english = 0;
	t.sum_score = 0;
}
int student_show_menu() //显示菜单
{
	int i = 0;
	printf("\n");
	for (i = 1; i < 50; i++)
		printf("*");
	printf("\n");
	printf("欢迎使用学生信息管理系统\n\n");
	printf("1.输入全部学生信息\n");
	printf("2.读取全部学生信息\n");
	printf("3.按姓名查询学生\n");
	printf("4.按学号查询学生\n");
	printf("5.按学号排序学生\n");
	printf("6.按总成绩排序学生\n");
	printf("7.添加学生信息\n");
	printf("8.删除学生信息\n");
	printf("0.退出系统\n\n");
	for ( i = 1; i < 50; i++)
		printf("*");
	printf("\n");
	return 0;
}

void student_input(LNode* head) //输入学生信息
{
	int n=0;
	int i = 0;
	printf("\n【1】输入全部学生信息\n");
	printf("输入学生个数：");
	scanf_s("%d", &n);
	LNode* p;
	LNode* r = head;
	printf("请输入学生信息：\n");
	for (i = 0; i < n; i++)
	{
		p = (LNode*)malloc(sizeof(LNode));
		p->next = NULL;
		printf("请输入学生姓名：");
		scanf_s("%s", p->data.names, maxsize);
		printf("请输入学号：");
		scanf_s("%d", &p->data.num);
		printf("请输入学生数学成绩：");
		scanf_s("%d", &p->data.math);
		printf("请输入学生英语成绩：");
		scanf_s("%d", &p->data.english);
		//int *sum = p->data.sum_score;
		p->data.sum_score = p->data.math + p->data.english;
		r->next = p;
		r = r->next;
		//free(p);		//若使用了此句，后续输出列表会出错。因为每个空间的数据都是有用的，所以不用free。
		printf("\n");
	}
	printf("\n添加学生信息成功！\n");
	//return head;
}

void student_show(LNode* head) //读取全部学生信息
{
	printf("\n【2】读取全部学生信息\n");
	LNode* p;
	p = head;
	if (p->next == NULL)
	{
		printf("\n当前没有任何学生信息记录! 请输入学生信息。\n");
		return;
	}
	printf("\n姓名\t\t学号\t\t数学成绩\t英语成绩\t总成绩\t\t\n");
	while (p->next != NULL)
	{
		p = p->next;
		printf("%s\t\t%d\t\t%d\t\t%d\t\t%d\t\t\n",
			p->data.names, p->data.num, p->data.math, p->data.english, p->data.sum_score);
	}
}

int name_find(LNode* head, student f) //按姓名查询学生
{
	printf("【3】按姓名查询学生\n");
	LNode* p;
	p = head;
	printf("请输入查找学生姓名：");
	scanf_s("%s", f.names, maxsize);
	while ((p->next != NULL) && strcmp(f.names, p->data.names)) //str1=str2，则返回零；若str1!=str2，则返回正数
	{
		p = p->next;
	}
	if ((p->next == NULL) && strcmp(f.names, p->data.names))
	{
		printf("\n抱歉，没有找到该学生的信息! \n");
		return 0;
	}
	else
	{
		printf("\n查找学生信息成功！\n");
		printf("\n姓名\t\t学号\t\t数学成绩\t英语成绩\t总成绩\t\t\n");
		printf("%s\t\t%d\t\t%d\t\t%d\t\t%d\t\t\n",
			p->data.names, p->data.num, p->data.math, p->data.english, p->data.sum_score);
		return 1;
	}
}

int num_find(LNode* head, student f2) //按学号查找学生
{
	printf("【4】按学号查询学生\n");
	LNode* p;
	p = head;
	printf("请输入查找学生学号：");
	scanf_s("%d", &f2.num);
	while ((p->next != NULL) && (p->data.num != f2.num))
	{
		p = p->next;
	}
	if ((p->next == NULL) && (p->data.num != f2.num))
	{
		printf("\n抱歉，没有找到该学生的信息! \n");
		return 0;
	}
	else
	{
		printf("\n查找学生信息成功！\n");
		printf("\n姓名\t\t学号\t\t数学成绩\t英语成绩\t总成绩\t\t\n");
		printf("%s\t\t%d\t\t%d\t\t%d\t\t%d\t\t\n",
			p->data.names, p->data.num, p->data.math, p->data.english, p->data.sum_score);
		return 1;
	}
}

void num_seq(LNode* head) //按学号排序
{
	printf("\n【5】按学号排序学生\n");
	LNode* newhead, * rear;
	newhead = head->next;
	rear = NULL;
	if (newhead == NULL || newhead->next == NULL)
	{
		printf("\n当前没有任何学生信息记录! 请输入学生信息。\n");
		return;
	}
	while (newhead != rear)
	{
		while (newhead->next != rear)
		{
			if (newhead->data.num > newhead->next->data.num)
			{
				int temp = newhead->data.num;
				newhead->data.num = newhead->next->data.num;
				newhead->next->data.num = temp;
				int temp1 = newhead->data.math;
				newhead->data.math = newhead->next->data.math;
				newhead->next->data.math = temp1;
				int temp2 = newhead->data.english;
				newhead->data.english = newhead->next->data.english;
				newhead->next->data.english = temp2;
				int temp3 = newhead->data.sum_score;
				newhead->data.sum_score = newhead->next->data.sum_score;
				newhead->next->data.sum_score = temp3;
				//char temp4_str = gets(newhead->data.names, sizeof(char));
				//char *temp4 = newhead->data.names; //先替换了此值，故第二个strcpy使用*temp4已经是新值了。
				student str;
				strcpy_s(str.names, maxsize, newhead->data.names);
				//gets_s(newhead->data.names,maxsize);
				//newhead->data.names = newhead->next->data.names;
				strcpy_s(newhead->data.names, maxsize, newhead->next->data.names);
				//newhead->next->data.names = temp4;
				strcpy_s(newhead->next->data.names, maxsize, str.names);
			}
			newhead = newhead->next;
		}
		rear = newhead;
		newhead = head->next;
	}
	printf("\n姓名\t\t学号\t\t数学成绩\t英语成绩\t总成绩\t\t\n");
	while (head->next != NULL)
	{
		head = head->next;
		printf("%s\t\t%d\t\t%d\t\t%d\t\t%d\t\t\n",
			head->data.names, head->data.num, head->data.math, head->data.english, head->data.sum_score);
	}
}

void sum_seq(LNode* head) //按总成绩排序
{
	printf("\n【6】按总成绩排序学生\n");
	LNode* newhead, * rear;
	newhead = head->next;
	rear = NULL;
	if (newhead == NULL || newhead->next == NULL)
	{
		printf("\n当前没有任何学生信息记录! 请输入学生信息。\n");
		return;
	}
	while (newhead != rear)
	{
		while (newhead->next != rear)
		{
			if (newhead->data.sum_score < newhead->next->data.sum_score)
			{
				int temp = newhead->data.num;
				newhead->data.num = newhead->next->data.num;
				newhead->next->data.num = temp;
				int temp1 = newhead->data.math;
				newhead->data.math = newhead->next->data.math;
				newhead->next->data.math = temp1;
				int temp2 = newhead->data.english;
				newhead->data.english = newhead->next->data.english;
				newhead->next->data.english = temp2;
				int temp3 = newhead->data.sum_score;
				newhead->data.sum_score = newhead->next->data.sum_score;
				newhead->next->data.sum_score = temp3;
				student str;
				strcpy_s(str.names, strlen(newhead->data.names) + 1, newhead->data.names);
				strcpy_s(newhead->data.names, strlen(newhead->next->data.names) + 1, newhead->next->data.names); //注意缓冲区长度，strlen()函数计算的字符串长度是不包括'\0’
				strcpy_s(newhead->next->data.names, strlen(str.names) + 1, str.names);
			}
			newhead = newhead->next;
		}
		rear = newhead;
		newhead = head->next;
	}
	printf("\n姓名\t\t学号\t\t数学成绩\t英语成绩\t总成绩\t\t\n");
	while (head->next != NULL)
	{
		head = head->next;
		printf("%s\t\t%d\t\t%d\t\t%d\t\t%d\t\t\n",
			head->data.names, head->data.num, head->data.math, head->data.english, head->data.sum_score);
	}
}

void stu_insert(LNode* head, student in) //增加学生信息
{
	printf("\n【7】添加学生信息\n");
	printf("请输入学生信息：\n");
	printf("请输入学生姓名：");
	scanf_s("%s", in.names, maxsize);
	printf("请输入学号：");
	scanf_s("%d", &in.num);
	printf("请输入学生数学成绩：");
	scanf_s("%d", &in.math);
	printf("请输入学生英语成绩：");
	scanf_s("%d", &in.english);
	in.sum_score = in.math + in.english;
	LNode* stu, * r;
	r = head;
	int d, dp = 0;
	printf("请输入要插入的位置：");
	scanf_s("%d", &d);
	while ((r != NULL) && (dp < d - 1))
	{
		r = r->next;
		dp = dp + 1;
	}
	if (r == NULL)
	{
		printf("\n插入错误，请重新输入。\n");
		return;
	}
	stu = (LNode*)malloc(sizeof(LNode));
	stu->data = in;
	stu->next = r->next;
	r->next = stu;
	printf("\n插入信息成功！\n");
}

void stu_del(LNode* head, student* dl) //删除学生信息
{
	printf("\n【8】删除学生信息\n");
	LNode* stu, * r;
	r = head;
	int d, dp = 0;
	printf("请输入要删除的位置：");
	scanf_s("%d", &d);
	while ((r->next != NULL) && (dp < d - 1))
	{
		r = r->next;
		dp++;
	}
	if (r->next == NULL)
	{
		printf("\n删除错误，请重新输入。\n");
		return;
	}
	stu = r->next;
	r->next = stu->next;
	*dl = stu->data; //此时应为*dl ,下面printf才能顺利输出
	free(stu);
	printf("删除%s成功!\n", dl->names);
	//return;
}