自写的学生信息管理系统

#include <iostream>
#include <iomanip>
#include <string>
#include <vector>
using namespace std;
const int NUM = 30;
const int CLASS_PRO = 5;

enum name_pro {chinese, matchs, english, physics, chemistry};//课程
//单个学生信息
class stq{
public:
	stq(){}
	stq(int num, string name, string name_class, double a, double b,
		double c, double d, double e)
	{
		this->num = num;
		this->name = name;
		this->name_class = name_class;
		sum[chinese] = a;
		sum[matchs] = b;
		sum[english] = c;
		sum[physics] = d;
		sum[chemistry] = e;
	}
	
	int getnum(){return num;}//返回学号
	string getname(){return name;}//返回名字
	string getname_class(){return name_class;}//返回班级
	double getsum(int sn){return sum[sn];}//返回单课程成绩

	int getgsum()//返回总成绩
	{
		double gsum = 0;
		for (int i = 0; i < CLASS_PRO; ++i)
		{
			gsum += sum[i];
		}
		return gsum;
	}
	int getpsum()//返回平均成绩
	{
		return getgsum() / CLASS_PRO;
	}
	void output()//输出学生信息
	{
		cout << num << "\t" << name << "\t" << name_class << "\t";
		for (int i = 0; i < CLASS_PRO; ++i)
		{
			cout << sum[i] << "\t";
		}
	}

	
private:
	int num;//学号
	string name;//姓名
	string name_class;//班级
	double sum[CLASS_PRO];//成绩
};

class str{
public:
    str()//构造函数
	{

	}

    void entry()//录入菜单
	{
		double sum[CLASS_PRO];
		cout << "请输入学生信息以及成绩!\n";
		cout << "学号：";
		int a;
		cin >> a;
		
		cout <<"姓名：";
		string b;
		cin >> b;

		cout << "成绩：\n";
		cout << "语文：";
		cin >> sum[0];

		cout << "数学：";
		cin >> sum[1];

		cout << "英语：";
		cin >> sum[2];

		cout << "物理：";
		cin >> sum[3];

		cout << "化学：";
		cin >> sum[4];

		cout <<"班级：";
		string d;
		cin >> d;

        stq student(a, b, d, sum[0], sum[1], sum[2], sum[3], sum[4]);
		bum.push_back(student);
	}

    void check()//查询菜单
	{
    	cout << "\n" << "--------------------\n"
	    	 << "查询-菜单:\n" << "【1】.学号\t"
	    	 << "\t【2】.课程\t" << "\t【0】.主菜单\n";
    	int o;
    	cin >> o;
    	switch (o)
		{
    	case 0: win_main(); break;
    	case 1: check_num(); break;
    	case 2: check_pro(); break;
    	default:
    		cout << "无效指令！\n";
	    	cin >> o;
	    	break;
		}
	}

    void check_num()//按学号查询
	{
		cout << "\n";
    	cout << "【1】.查询该学生成绩\t【2】.查询该学生平均成绩\n【0】.返回主菜单\n";
    	int a;
    	cin >> a;
		switch (a)
		{
		case 0: win_main(); break;
		case 1: check_student_sum(); break;
		case 2: check_student_psum(); break;
		}
	}
	
	void check_student_sum()//查询该学生全部成绩
	{
		cout << "请输入学号：\n";
		int n;
		cin >> n;
		cout << "-------------------------学生信息------------------------\n";
		cout << "学号\t" << "姓名\t" << "班级\t" << "语文\t" <<
			"数学\t" << "英语\t" << "物理\t" << "化学\t" << endl;
		bum[n - 1].output();
		cout << "\n【1】.返回上一级\t【2】.主菜单\n";
		int o;
		cin >> o;
		switch (o)
		{
		case 1: check_num(); break;
		case 2: win_main(); break;
		}
	}

	void check_student_psum()//查询平均成绩
	{
		cout << "请输入学号：\n";
		int n;
		cin >> n;
		cout << "-------------------------学生信息------------------------\n";
		cout << bum[n - 1].getname() << "学生的平均成绩：" << bum[n - 1].getpsum() << endl;
		cout << "【1】.返回上一级\t【2】.主菜单\n";
		int o;
		cin >> o;
		switch (o)
		{
		case 1: check_num(); break;
		case 2: win_main(); break;
		}
	}

	void check_pro()//按课程查询
	{
		cout << "\n";
    	cout << "【1】.查询该课程平均成绩\t【2】.查询该课程及格率\n";
		cout << "【3】.查询该课程最低成绩\t【4】.查询该课程最高成绩\n【0】.返回主菜单\n";
    	int a;
    	cin >> a;
		switch (a)
		{
		case 0: win_main(); break;
		case 1: check_pro_psum(); break;
		case 2: check_pro_gsum(); break;
		case 3: check_pro_min(); break;
		case 4: check_pro_max(); break;
		}
	}

	void check_pro_psum()//该科目平均成绩
	{
		cout << "\n请输入查询科目：\n";
		cout << "【0】.语文\t【1】.数学\t【2】.英语\t【3】.物理\t【4】.化学\n";
		int n;
		cin >> n;
		double sum_all = 0;
        for (int i = 0; i != bum.size(); ++i)
			sum_all += bum[i].getsum(n);
		double sum_p = sum_all / bum.size();
		switch (n)
		{
		case 0: 
			{
				cout << "语文平均分为：" << sum_p << endl;
			}
			break;
		case 1: 
			{
				cout << "数学平均分为：" << sum_p << endl;
			}
			break;
		case 2: 
			{
				cout << "英语平均分为：" << sum_p << endl;
			}
			break;
		case 3: 
			{
				cout << "物理平均分为：" << sum_p << endl;
			}
			break;
		case 4: 
			{
				cout << "化学平均分为：" << sum_p << endl;
			}
			break;
		default:
			cout << "无效指令！" << endl;
			cin >> n;
			break;
		}

        cout << "【1】.返回上一级\t【2】.主菜单\n";
		int o;
		cin >> o;
		switch (o)
		{
		case 1: check_pro(); break;
		case 2: win_main(); break;
		}
	}
	void check_pro_gsum()//该课程及格率
	{
		cout << "\n请输入查询科目：\n";
		cout << "【0】.语文\t【1】.数学\t【2】.英语\t【3】.物理\t【4】.化学\n";
		int n;
		cin >> n;
		double sum_all = 0;
        for (int i = 0; i != bum.size(); ++i)
		{
			if (bum[i].getsum(n) > 60)
				++sum_all;
		}
		double sum_p = sum_all / bum.size();
		cout << fixed << setprecision(4);
		switch (n)
		{
		case 0: 
			{
				cout << "语文及格率为：" << sum_p << endl;
			}
			break;
		case 1: 
			{
				cout << "数学及格率为：" << sum_p << endl;
			}
			break;
		case 2: 
			{
				cout << "英语及格率为：" << sum_p << endl;
			}
			break;
		case 3: 
			{
				cout << "物理及格率为：" << sum_p << endl;
			}
			break;
		case 4: 
			{
				cout << "化学及格率为：" << sum_p << endl;
			}
			break;
		default:
			cout << "无效指令！" << endl;
			cin >> n;
			break;
		}
		cout << "【1】.返回上一级\t【2】.主菜单\n";
		int o;
		cin >> o;
		switch (o)
		{
		case 1: check_pro(); break;
		case 2: win_main(); break;
		}
	}
	void check_pro_min()//该课程最低成绩
	{
		cout << "\n请输入查询科目：\n";
		cout << "【0】.语文\t【1】.数学\t【2】.英语\t【3】.物理\t【4】.化学\n";
		int n;
		cin >> n;
		double min = bum[0].getsum(n);
		for (int i = 0; i != bum.size(); ++i)
		{
			if (min > bum[i].getsum(n))
				min = bum[i].getsum(n);
		}
		switch (n)
		{
		case 0: 
			{
				cout << "语文最低成绩为：" << min << endl;
			}
			break;
		case 1: 
			{
				cout << "数学最低成绩为：" << min << endl;
			}
			break;
		case 2: 
			{
				cout << "英语最低成绩为：" << min << endl;
			}
			break;
		case 3: 
			{
				cout << "物理最低成绩为：" << min << endl;
			}
			break;
		case 4: 
			{
				cout << "化学最低成绩为：" << min << endl;
			}
			break;
		default:
			cout << "无效指令！" << endl;
			cin >> n;
			break;
		}

	}
	void check_pro_max()//该课程最高成绩
	{
		cout << "\n请输入查询科目：\n";
		cout << "【0】.语文\t【1】.数学\t【2】.英语\t【3】.物理\t【4】.化学\n";
		int n;
		cin >> n;
		double max = bum[0].getsum(n);
		for (int i = 0; i != bum.size(); ++i)
		{
			if (max < bum[i].getsum(n))
				max = bum[i].getsum(n);
		}
		switch (n)
		{
		case 0: 
			{
				cout << "语文最高成绩为：" << max << endl;
			}
			break;
		case 1: 
			{
				cout << "数学最高成绩为：" << max << endl;
			}
			break;
		case 2: 
			{
				cout << "英语最高成绩为：" << max << endl;
			}
			break;
		case 3: 
			{
				cout << "物理最高成绩为：" << max << endl;
			}
			break;
		case 4: 
			{
				cout << "化学最高成绩为：" << max << endl;
			}
			break;
		default:
			cout << "无效指令！" << endl;
			cin >> n;
			break;
		}

		cout << "【1】.返回上一级\t【2】.主菜单\n";
		int o;
		cin >> o;
		switch (o)
		{
		case 1: check_pro(); break;
		case 2: win_main(); break;
		}
	}

	void win_main()//主菜单
	{
		cout << "\n" << "--------------------\n"
		    	 << "******系统菜单******\n"
		    	 << "【1】.录入\t【2】.查询\t【0】.退出" << endl;
	    	int p;
	    	cin >> p;
	    	switch (p)
			{
	    	case 0: return;
	    	case 1: entry(); break;
	    	case 2: check(); break;
	    	default: 
		    	cout << "无效指令！\n";
		    	cin >> p;
		    	break;
			}
	}


    void win()//登陆界面
	{
    	cout << "**学生成绩管理系统**\n"
		 << "请输入密码：";
    	string pwd;
    	cin >> pwd;
    	while (pwd != "123")
		{
	    	cout << "输入指令错误！请重新输入！\n";
	    	cin >> pwd;
		}
    	while (1)
		{
			win_main();
		}
	}

private:
	vector<stq> bum;
};

int main()
{
	str s;
	s.win();
	return 0;
}