#include<stdio.h>
#define maxsize 100
struct student{
	int num;
	char name;
	int math,chin,eng;
	int average;
};

int count = 0;

void new_students(struct student students[])
{
	int i, n;
	if (count == maxsize){
		printf("the number isfull");
		return;
	}
	printf("the number is n");
	scanf("%d", &n);
	for (i = 0; i < n; i++){
		printf("the student's num");
		scanf("%d", &students[i].num);
		printf("the student's name");
		scanf("%s",&students[i].name);
		printf("the student's math");
		scanf("%d", &students[i].math);
		printf("the student's chin");
		scanf("%d", &students[i].chin);
		printf("the student's eng");
		scanf("%d", &students[i].eng);
		
		count++;
	}
}
void out_input(struct student students[])
{
	int i;
	if (count == 0){
		printf("count of students is 0");
		return;
	}
	
	printf("num\t name\t math\t chin\t eng\t average\n");
	for (i = 0; i < count; i++){
		printf("%d\t", students[i].num);
		printf("%s\t", students[i].name);
		printf("%d\t", students[i].math);
		printf("%d\t", students[i].chin);
		printf("%d\t", students[i].eng);
		
		printf("%d\t\n", students[i].average);






	}
	getchar();
	
}

void average(struct student students[])
{
	int i;
	for (i = 0; i < count; i++)
	{
		students[i].average = (students[i].eng + students[i].math + students[i].chin) / 3;
		
	}
		

	
}
void sort(struct student s[])
{
	struct student temp;
	int i,  j;
	for (i = 0; i < count; i++)
	{
		for (j = 0; j < i - j - 1; j++)
		if (s[j].average>s[j + 1].average){
			temp = s[j];
			s[j] = s[j + 1];
			s[j + 1] = temp;

		}
	}

}
void modify(struct student *p)
{
	int num, course, score, i;
	printf("input the new student");
	scanf("%d", &num);
	printf("chioce the course :1math 2.chin,3.eng");
	scanf("%d", &course);
	printf("input the new score");
	scanf("%d", &score);
	for (i = 0; i < count; i++, p++)
	{
		if (p->num == num)
			break;
		if (i<count)
			switch (course)
		{
			case 1:p->math = score; 
				break;
			case 2:p->chin = score;
				break;
			case 3:p->eng = score;
				break;
		}
    }
}
void search_student(struct student students[], int num)
{
	int i, flag = 0;
	if (count == 0){
		printf("zhe xue sheng shu mu is0");
		return;
	}
	for (i = 0; i < count;i++)
	if (students[i].num == num)
	{
		flag = 1;
		break;
	}
	if (flag)
	{
		printf("num:%d", students[i].num);
		printf("name:%s", students[i].name);
		printf("math:%d", students[i].math);
		printf("chin:%d", students[i].chin);
		printf("eng:%d", students[i].eng);
		printf("average:%d", students[i].average);


	}
	else
		printf("no found");

}




void new_students(struct student students[]);
void out_input(struct student students[]);
void search_student(struct student students[], int num);
void modify(struct student *p);
void average(struct student students[]);
void sort(struct student s[]);
int main()
{
	struct student students[maxsize];
	new_students(students);
	average(students);
	out_input(students);
	sort(students);
	out_input(students);
	modify(students);


	out_input(students);


	return 0;
}