学生成绩管理系统V1.0

某班有最多不超过30人（具体人数由键盘输入）参加某门课程的考试，用一维数组作函数参数编程实现如下学生成绩管理：

（1）录入每个学生的学号和考试成绩；

（2）计算课程的总分和平均分；

（3）按成绩由高到低排出名次表；

（4）按学号由小到大排出成绩表；

（5）按学号查询学生排名及其考试成绩；

（6）按优秀（90~100）、良好（80~89）、中等（70~79）、及格（60~69）、不及格（0~59）5个类别，统计每个类别的人数以及所占的百分比；

（7）输出每个学生的学号、考试成绩。

#include 
#include 
using namespace std;
void input(int a[], float b[],int);
void caculate(float a[],int);
void sort_in_descending_order_by_score(int a[], float b[],int);
void sort_in_ascending_order_by_number(int a[],float b[],int);
void search(int a[],float b[],int);
void statistic(float a[],int);
int main()
{
	int n;
	cout << "Input student number(n<30):";
	cin >> n;
	int choice;
	int xvehao[30];
	float score[30];
	while (1)
	{
		cout << endl;
		cout << "Management for Students' scores" << endl;
		cout << "1.Input record" << endl;
		cout << "2.Caculate total and average score of course" << endl;
		cout << "3.Sort in descending order by score" << endl;
		cout << "4.Sort in ascending order by number" << endl;
		cout << "5.Search by number" << endl;
		cout << "6.Statistic analysis" << endl;
		cout << "7.List record" << endl;
		cout << "0.Exit" << endl;
		cout << "Please Input your choice:";
		cin >> choice;

		if (choice == 1)input(xvehao, score, n);
		else if (choice == 2)caculate(score, n);
		else if (choice == 3)sort_in_descending_order_by_score(xvehao, score, n);
		else if (choice == 4)sort_in_ascending_order_by_number(xvehao, score, n);
		else if (choice == 5)search(xvehao, score, n);
		else if (choice == 6)statistic(score, n);
		else if (choice == 7)sort_in_ascending_order_by_number(xvehao, score, n);
		else if (choice == 0)break;
		else
		{
			cout << "Please input any number from 0 to 7!"<> a[i] >> b[i];
	}
	
}
void caculate(float a[], int n)
{
	float sum=0,aver;
	int i;
	for (i = 1; i <= n; i++)
	{
		sum += a[i];
	}
	aver = sum / n;
	cout << "sum=" << sum << " , aver=" << fixed << setprecision(2) << aver;
	cout << endl;
}
void sort_in_descending_order_by_score(int a[], float b[], int n)
{
	int i, j,k;
	for (i = 1; i <= n; i++)
	{
		k = i;
		for (j = i+1; j <= n ; j++)
		{
			if (b[k] < b[j])k = j;
		}
		int x = a[i], y = b[i];
		a[i] = a[k]; b[i] = b[k];
		a[k] = x; b[k] = y;
	}
	for (i = 1; i <= n; i++)
	{
		cout << a[i] << " " << b[i] << endl;
	}
}
void sort_in_ascending_order_by_number(int a[], float b[], int n)
{
	int i, j,k;
	for (i = 1; i <= n; i++)
	{
		k = i;
		for (j = i + 1; j <= n; j++)
		{
			if (a[j] < a[k])k = j;
		}
		int x = a[i], y = b[i];
		a[i] = a[k]; b[i] = b[k];
		a[k] = x; b[k] = y;
	}
	for (i = 1; i <= n; i++)
	{
		cout << a[i] << " " << b[i] << endl;
	}
}
void search(int a[], float b[], int n)
{
	int number;
	cin >> number;
	int i,k;
	for (i = 1; i <= n; i++)
	{
		if (a[i] == number)
		{
			cout << a[i] << " " << b[i]<= 90 && a[i] <= 99)B++;
		else if (a[i] >= 80 && a[i] <= 89)C++;
		else if (a[i] >= 70 && a[i] <= 79)D++;
		else if (a[i] >= 60 && a[i] <= 69)E++;
		else F++;
	}
	cout << "<60 "  << F<< " " <