C++实现：学生管理系统（详细解析）

我爱OJ 2023-07-09 原文

1.题目要求

学生成绩管理系统

（1）增加记录：要求可以连续增加多条记录。
（2）查找：可以根据姓名（或学号）查找某个学生的课程成绩，查找某门课程成绩处于指定分数段内的学生名单等等。可以实现模糊查询，即输入名字的一部
分，可以列出满足条件的所有记录。再从这个记录中进行二次选择。
（3）删除一个学生的记录：要求可以先查找，再删除。删除前，要求用户确认。
（4）成绩修改：若输入错误可进行修改；要求可以先查找，再修改。
（5）统计分析：对某个班级学生的单科成绩进行统计，求出平均成绩；求平均成绩要求实现函数的重载，既能求单科的平均成绩，又能求三科总分的平均成绩。
求出一门课程标准差和合格率；
（6）排序功能：要求按总分进行排序（从高到低），若总分相同，则按数学排序；
若总分和数学相同，则按物理排序；若总分和各科成绩都相同，则按学号排
序；
（7）文件操作：可以打开文件，显示班级的所有学生信息；可以将增加或修改后的成绩重新写入文件；可以将排序好的信息写入新的文件；

2.需求分析

基本思路

设计一个学生的类。类的设计测试数据的记录和将要实现的功能。学生成绩

管理系统有若干学生成绩记录组成，学生一条记录包括：学号、姓名、数学

成绩、物理成绩和英语成绩。主函数显示功能菜单，供用户选择操作。每步操

作之前，都要显示菜单。在主函数中调用类的方法

编译环境
在DEV-C++上运行通过

3.整体设计

【1】录入学生信息
【2】显示学生信息
【3】修改学生信息
【4】查找学生信息
【5】删除学生信息
【6】学生信息文件
【7】成绩排序功能
【8】存入新文件
【9】统计分析成绩

4.详细设计

主函数设计

int main()
{
	StudentList stuList;
	stuList.init(); //读入文件数据初始化
	stuList.menu(); //打开主菜单
	return 0;
}

效果如下

学科科目类

class Subject
{
	public:
		string proName;  //学科名
		double proScore; //分数
		void showCpInfo()
		{
			cout << left << setw(45) << proName;
			cout << left << setw(6) <<  proScore << endl;
		}
		//输出属性名，只显示总积分
		static void showHeader()
		{
			cout << left << setw(45) << "科目";
			cout << left << setw(6) <<  "分数" <<endl;
		}
};

效果如下

主菜单

void menu()
		{
			string sel = "0";
			system("cls");
			cout << "\t\t\t**********欢迎来到学生成绩管理系统**********" << endl;
			cout << "\t\t\t你可以进行以下操作:" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             1   添加学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             2   删除学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             3   修改学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             4   查询学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             5   显示信息列表             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             6   统计学生数据             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             7   清空系统数据             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             0   退出                     |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t请选择【0-7】：";
			cin >> sel;
			while(sel != "0" && sel != "1" && sel != "2" && sel != "3" && sel != "4" && sel != "5" && sel != "6" && sel != "7")
			{
				cout << "\t\t\t输入不合法,请重新选择【0-7】：";
				cin >> sel;
			}
			if(sel == "1")
			{
				this->insertList();
				this->menu();
			}
			else if(sel == "2")
			{
				this->deleteList();
				this->menu();
			}
			else if(sel == "3")
			{
				this->updateList();
				this->menu();
			}
			else if(sel == "4")
			{
				this->selectList();
				this->menu();
			}
			else if(sel == "5")
			{
				this->displayList();
				this->menu();
			}
			else if(sel == "6")
			{
				this->statisticList();
				this->menu();
			}
			else if(sel == "7")
			{
				this->clearList();
				this->menu();
			}
			else if(sel == "0")
			{
				exit(0);
			}
		}

效果如下

读取文件与写入文件

void readFile()
		{
			ifstream ifs;
			ifs.open("stuList.txt", ios::in);
			int n = 0; //用来接收学生数量的值
			ifs >> n;
			for(int i = 0; i < n; i++)
			{
				Student s;
				ifs >> s.stuNum >> s.stuName >> s.gender >> s.gradeNum >> s.department >> s.classNum >> s.cpNum >> s.score;
				for(int j = 0; j < s.cpNum; j++)
				{
					Subject cp;
					ifs >> cp.proName >> cp.proScore;
					s.cps.push_back(cp);
				}
				stuList.push_back(s);
			}
			ifs.close();
		}
		//写入文件
		void writeFile()
		{
			ofstream ofs;
			ofs.open("stuList.txt", ios::out);
			ofs << stuList.size() << endl; //先写入学生数量
			for (int i = 0; i < stuList.size(); i++)
			{
				ofs << stuList[i].stuNum << " " <<  stuList[i].stuName << " " << stuList[i].gender
				    << " " << stuList[i].gradeNum << " " << stuList[i].department << " " << stuList[i].classNum
				    << " " << stuList[i].cpNum << " " << stuList[i].score << endl;
				for(int j = 0; j < stuList[i].cps.size(); j++)
				{
					ofs << stuList[i].cps[j].proName << " " << stuList[i].cps[j].proScore << endl;
				}
			}
			ofs.close();
		}

效果如下

添加学生信息

void insertList()
		{
			while(true)
			{
				system("cls");
				cout << "\t\t**********************欢迎来到添加学生信息功能*************************" << endl;
				cout<< "\t\t学生基本信息一览表："<<endl;
				displayStu();
				cout<<endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t1 添加学生信息" << endl;
				cout << "\t\t2 返回主菜单" << endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t请选择【1-2】：";
				string sel;
				cin >> sel;
				while(sel != "1" && sel != "2")
				{
					cout << "\t\t输入不合法,请重新输入【1-2】：";
					cin >> sel;
				}
				if(sel == "1")
				{
					string flag = "1";
					while (flag == "1")
					{
						cout << "\t\t输入学生信息："<<endl;
						cout << "\t\t学号：";
						Student s;
						bool check = false;
						do
						{
							check = false;
							cin >> s.stuNum;
							for(int i = 0; i < stuList.size(); ++i)
							{
								if(s.stuNum == stuList[i].stuNum)
								{
									cout<<"\t\t该学号已存在，请重新输入：";
									check = true;
									break;
								}
							}
						}
						while(check);
						cout << "\t\t姓名：";
						cin >> s.stuName;
						cout << "\t\t性别：";
						cin >> s.gender;
						cout << "\t\t年级：";
						cin >> s.gradeNum;
						cout<<"\t\t专业：";
						cin >> s.department;
						cout<<"\t\t班级：";
						cin >> s.classNum;
						s.score = 0;
						string option = "1";
						cout<<"\t\t是否添加成绩信息？（1 是 0 否）"<<endl;
						cout << "\t\t请进行选择【0-1】：";
						cin >> option;
						while(option != "0" && option != "1")
						{
							cout << "\t\t输入不合法,请重新选择【0-1】：";
							cin >> option;
						}
						if(option == "1")
						{
							int cnt = 0;
							while(option == "1")
							{
								cnt++;
								Subject cp;
								cout<<"\t\t第"<<cnt<<"科科目名称：";
								cin>>cp.proName;
								cout<<"\t\t第"<<cnt<<"科科目成绩：";
								cin>>cp.proScore;
								s.cps.push_back(cp);
								cout << "\t\t该科成绩信息添加成功！是否继续添加？（1 是 0 否）" << endl;
								cout << "\t\t请进行选择【0-1】：";
								cin >> option;
								while(option != "0" && option != "1")
								{
									cout << "\t\t输入不合法,请重新选择【0-1】：";
									cin >> option;
								}
							}
						}
						for(int i = 0; i < s.cps.size(); i++)
						{
							s.score += s.cps[i].proScore;
						}
						if(s.cps.size() > 0) s.score /= s.cps.size(); //计算平均分
						s.cpNum = s.cps.size();
						stuList.push_back(s);
						writeFile();
						cout << "\n\t\t该名学生信息添加成功！是否继续添加？（1 是 0 否）" << endl;
						cout << "\t\t请进行选择【0-1】：";
						cin >> flag;
						while(flag != "0" && flag != "1")
						{
							cout << "\t\t输入不合法,请重新选择【0-1】：";
							cin >> flag;
						}
					}
					cout << "\t\t";
					system("pause");
				}
				else
				{
					break;
				}
			}
		}

效果如下

删除学生信息

void deleteList()
		{
			while (true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到删除学生信息功能***********************" << endl;
				string sel = "0";
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 按学号删除" << endl;
				cout << "\t\t2 按姓名删除" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}
				if (sel == "1")
				{
					string keyNum;
					bool flag = false;
					cout << "\t\t请输入待删除学生的学号：";
					cin >> keyNum;
					for (vector<Student>::iterator it = stuList.begin(); it != stuList.end(); ++it)
					{
						if (it->stuNum == keyNum)
						{
							flag = true;
							cout << "\t\t待删除学生的信息如下：" << endl;
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							Student::showHeader();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							it->showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout << "\t\t确认删除？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}
							if (ch == "0") break;
							else
							{
								stuList.erase(it);
								writeFile();
								cout << "\t\t删除成功！" << endl;
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法删除！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else if (sel == "2")
				{
					string keyName;
					bool flag = false;
					cout << "\t\t请输入待删除学生的姓名：";
					cin >> keyName;
					for (vector<Student>::iterator it = stuList.begin(); it != stuList.end(); ++it)
					{
						if (it->stuName == keyName)
						{
							flag = true;
							cout << "\t\t待删除学生的信息如下：" << endl;
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t\t";
							Student::showHeader();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							it->showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout << "\t\t确认删除？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}
							if (ch == "0") break;
							else
							{
								stuList.erase(it);
								writeFile();
								cout << "\t\t删除成功！" << endl;
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法删除！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else
				{
					break;
				}
			}
		}

效果如下

修改学生信息

void updateList()
		{
			while(true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到修改学生信息功能***********************" << endl;
				string sel = "0";
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 修改学生基本信息" << endl;
				cout << "\t\t2 修改学生成绩信息" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}

				if(sel == "1")
				{
					bool flag = false;
					string keyNum;
					cout << "\t\t请输入待修改学生的学号：";
					cin >> keyNum;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuNum == keyNum)
						{
							flag = true;
							cout << "\t\t待修改学生基本信息如下：" << endl;
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							Student::showHeader();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							stuList[i].showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							
							Student s = stuList[i];
							cout << "\t\t请输入修改后的学号：";
							bool check = false;
							do
							{
								check = false;
								cin >> s.stuNum;
								for(int j = 0; j < stuList.size(); ++j)
								{
									if(s.stuNum == stuList[j].stuNum && i != j)
									{
										cout<<"\t\t该学号已被录入，请重新输入学号：";
										check = true;
										break;
									}
								}
							}
							while(check);
							cout << "\t\t请输入修改后的姓名：";
							cin >> s.stuName;
							cout << "\t\t请输入修改后的性别：";
							cin >> s.gender;
							cout << "\t\t请输入修改后的年级：";
							cin >> s.gradeNum;
							cout<<"\t\t请输入修改后的专业：";
							cin >> s.department;
							cout<<"\t\t请输入修改后的班级：";
							cin >> s.classNum;
							cout << "\t\t是否确认修改？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}

							if (ch == "0") break;
							else
							{
								stuList[i] = s;
								cout << "\t\t修改成功！" << endl;
								writeFile();
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法修改！\n" << endl;
				}
				else if(sel == "2")
				{
					bool flag = false;
					string keyNum;
					cout << "\t\t请输入待修改学生的学号：";
					cin >> keyNum;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuNum == keyNum)
						{
							flag = true;
							cout << "\t\t待修改学生成绩信息如下：" << endl;
							cout << "\t\t----------------------------------------------------------" << endl;
							cout<<"\t\t";
							cout << left << setw(8) <<  "编号";
							Subject::showHeader();
							cout << "\t\t----------------------------------------------------------" << endl;
							for(int j = 0; j < stuList[i].cps.size(); j++)
							{
								cout<<"\t\t";
								cout << left << setw(8) << j + 1;
								stuList[i].cps[j].showCpInfo();
							}
							cout << "\t\t----------------------------------------------------------" << endl;
							Student s = stuList[i];
							cout << "\t\t请选择修改方式："<<endl;
							string option = "1";
							cout << "\t\t-------------------------------" << endl;
							cout << "\t\t1 基于该学生原有成绩信息进行修改" << endl;
							cout << "\t\t2 清空该学生所有科目及成绩信息" << endl;
							cout << "\t\t-------------------------------" << endl;
							cout << "\t\t请进行选择【1-2】：";
							cin >> option;
							while(option != "1" && option != "2")
							{
								cout << "\t\t输入不合法,请重新选择【1-2】：";
								cin >> option;
							}
							Subject cp;
							if(option == "1")
							{
								s.cps.clear();
								s.score = 0;
								s.cpNum = 0;
								cout<<"\t\t输入修改后的学科成绩信息："<<endl;
								int cnt = 0;
								while(option == "1")
								{
									cnt++;
									cout<<"\t\t第"<<cnt<<"科科目名称：";
									cin>>cp.proName;
									cout<<"\t\t第"<<cnt<<"科科目成绩：";
									cin>>cp.proScore;
									s.cps.push_back(cp);
									cout << "\n\t\t添加成功！是否继续添加？（1 是 0 否）" << endl;
									cout << "\t\t请进行选择【0-1】：";
									cin >> option;
									while(option != "0" && option != "1")
									{
										cout << "\t\t输入不合法,请重新选择【0-1】：";
										cin >> option;
									}
								}
							}
							else if(option == "2")
							{
								s.cps.clear();
								s.score = 0;
								s.cpNum = 0;
							}
							//计算平均分
							for(int i = 0; i < s.cps.size(); i++)
							{
								s.score += s.cps[i].proScore;
							}
							if(s.cps.size() > 0) s.cpNum = s.cps.size();
							cout << "\t\t是否确认修改？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}
							if (ch == "0") break;
							else
							{
								stuList[i] = s;
								cout << "\t\t修改成功！" << endl;
								writeFile();
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法修改！\n" << endl;
				}
				else
				{
					break;
				}
				cout << "\t\t";
				system("pause");
			}
		}

效果如下

显示信息列表

void selectList()
		{
			while (true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到查询学生信息功能************************" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 按学号查询" << endl;
				cout << "\t\t2 按姓名查询" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				string sel = "0";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}
				if (sel == "1")
				{
					string keyNum;
					bool flag = false;
					cout << "\t\t请输入待查询学生的学号：";
					cin >> keyNum;
					cout << "\t\t查询结果如下：" << endl;
					cout<<"\t\t基本信息："<<endl;
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					cout<<"\t\t";
					Student::showHeader();
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuNum == keyNum)
						{
							flag = true;
							cout<<"\t\t";
							stuList[i].showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<endl;
							cout<<"\t\t"<<stuList[i].stuName<<"成绩信息："<<endl;
							cout << "\t\t----------------------------------------------------------" << endl;
							cout<<"\t\t";
							cout << left << setw(8) <<  "编号";
							Subject::showHeader();
							cout << "\t\t----------------------------------------------------------" << endl;
							for(int j = 0; j < stuList[i].cps.size(); j++)
							{
								cout<<"\t\t";
								cout << left << setw(8) << j + 1;
								stuList[i].cps[j].showCpInfo();
							}
							cout << "\t\t----------------------------------------------------------" << endl;
							break;
						}
					}
					if (!flag) cout << "\t\t查无此人！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else if (sel == "2")
				{
					string keyName;
					bool flag = false;
					cout << "\t\t请输入待查询联系人的姓名：";
					cin >> keyName;
					cout << "\t\t查询结果如下：" << endl;
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					cout<<"\t\t";
					Student::showHeader();
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuName == keyName)
						{
							flag = true;
							cout<<"\t\t";
							stuList[i].showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<endl;
							cout<<"\t\t"<<stuList[i].stuName<<"成绩信息："<<endl;
							cout << "\t\t----------------------------------------------------------" << endl;
							cout<<"\t\t";
							cout << left << setw(8) <<  "编号";
							Subject::showHeader();
							cout << "\t\t----------------------------------------------------------" << endl;
							for(int j = 0; j < stuList[i].cps.size(); j++)
							{
								cout<<"\t\t";
								cout << left << setw(8) << j + 1;
								stuList[i].cps[j].showCpInfo();
							}
							cout << "\t\t----------------------------------------------------------" << endl;
							break;
						}
					}
					if (!flag) cout << "\t\t查无此人！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else 
				{
					break; 
				}
			}
		}
		//遍历学生列表
		void displayStu()
		{
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			cout<<"\t\t";
			Student::showHeader();
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			for (int i = 0; i < stuList.size(); i++)
			{
				cout << "\t\t";
				stuList[i].showStuInfo();
			}
			cout << "\t\t-----------------------------------------------------------------------" << endl;
		}
		//查询获奖信息
		void displayCp()
		{
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			cout<<"\t\t";
			cout << left << setw(12) << "学号";
			cout << left << setw(10) <<  "姓名";
			Subject::showHeader();
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			for (int i = 0; i < stuList.size(); i++)
			{
				for(int j = 0; j < stuList[i].cps.size(); j++)
				{
					cout << "\t\t";
					cout << left << setw(12) << stuList[i].stuNum;
					cout << left << setw(10) <<  stuList[i].stuName;
					stuList[i].cps[j].showCpInfo();
				}
			}
			cout << "\t\t-----------------------------------------------------------------------" << endl;
		}

显示学生列表

void displayList()
		{
			system("cls");
			cout << "\t\t***********************欢迎来到显示信息列表功能************************" << endl;
			cout << "\t\t表1：学生基本信息一览表"<<endl;
			this->displayStu();
			cout << "\n\t\t表2：学生成绩信息一览表"<<endl;
			this->displayCp();
			cout << "\t\t";
			system("pause");
		}

效果如下

将学生列表按学号升序排列

static bool cmpNum(const Student& s1,const Student& s2)
		{
			return s1.stuNum < s2.stuNum;
		}

将学生列表按平均分降序排列，平均分相同的再按学号升序排列

static bool cmpscore(const Student& s1,const Student& s2)
		{
			if(s1.stuNum != s2.stuNum) return s1.score > s2.score;
			else return s1.stuNum < s2.stuNum;
		}

统计学生数据

void statisticList()
		{
			while(true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到统计学生数据功能************************" << endl;
				string sel = "0";
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 按学号排序" << endl;
				cout << "\t\t2 按平均分排序" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}
				if(sel == "1")
				{
					sort(stuList.begin(), stuList.end(), cmpNum);
					cout<<"\t\t按学号升序排列如下："<<endl;
					this->displayStu();
					int numMale = 0, numFemale = 0;
					for(int i = 0; i < stuList.size(); ++i)
					{
						if(stuList[i].gender == "男") numMale++;
						else if(stuList[i].gender == "女") numFemale++;
					}
					cout<<"\t\t一共 " << stuList.size() << " 人，其中男生 " << numMale << " 人，女生 " << numFemale << " 人。"<<endl;
					cout << "\t\t";
					system("pause");
				}
				else if(sel == "2")
				{
					sort(stuList.begin(), stuList.end(), cmpscore);
					cout<<"\t\t按平均分降序排列如下："<<endl;
					this->displayStu();
					vector<int> z(10);
					double totalscore = 0;
					for(int i = 0; i < stuList.size(); ++i)
					{
						totalscore += stuList[i].score;
						if(0 <= stuList[i].score && stuList[i].score < 60) z[0]++;
						else if(60 <= stuList[i].score && stuList[i].score < 70) z[1]++;
						else if(70 <= stuList[i].score && stuList[i].score < 80) z[2]++;
						else if(80 <= stuList[i].score && stuList[i].score < 90) z[3]++;
						else z[4]++;
					}
					cout<<"\t\tscore < 60 -------------- " << z[0] << " 人" << endl;
					cout<<"\t\t60 <= score < 70 --------- " << z[1] << " 人" << endl;
					cout<<"\t\t70 <= score < 80 --------- " << z[2] << " 人" << endl;
					cout<<"\t\t80 <= score < 90 --------- " << z[3] << " 人" << endl;
					cout<<"\t\tscore >= 90 ------------- " << z[4] << " 人" << endl;
					cout<<"\t\t所有学生平均分为："<<totalscore / stuList.size()<<endl;
					cout<<"\t\t"<<stuList.back().gradeNum<<"级"<<stuList.back().department<<stuList.back().classNum<<"班---";
					cout<<stuList.back().stuName<<"平均分最低，为："<<stuList.back().score<<"分"<<endl;
					cout<<"\t\t"<<stuList.front().gradeNum<<"级"<<stuList.front().department<<stuList.front().classNum<<"班---";
					cout<<stuList.front().stuName<<"平均分最高，为："<<stuList.front().score<<"分"<<endl;
					cout << "\t\t";
					system("pause");
				}
				else
				{
					break;
				}
			}
		}

效果如下

清空系统数据

void clearList()
		{
			while (true)
			{
				string sel = "0";
				system("cls");
				cout << "\t\t**************欢迎来到清空系统数据功能***************" << endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t1 确认清空系统数据" << endl;
				cout << "\t\t2 返回主菜单" << endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t请慎重选择【1-2】：";
				cin >> sel;
				while(sel != "1" && sel != "2")
				{
					cout << "\t\t输入不合法,请重新输入【1-2】：";
					cin >> sel;
				}
				if (sel == "1")
				{
					stuList.clear();
					cout << "\t\t清空成功！" << endl;
					cout << "\t\t";
					system("pause");
					writeFile();
				}
				else 
				{
					break;
				}
			}
		}
};

效果如下

5.总结

实现亮点：

界面简洁、每次操作完一个功能可进行一次清屏操作，仅保留功能提示文字；

排序功能实现了多种排序方式：单科排序以及总成绩排序

统计功能实现了平均分、及格人数、标准差等数据的统计

输出新文件时可以新建文件名，保存路径，输出文件同时统计数据：包括总分平均分、及格人数、标准差等；

读入文件允许输入文件路径进行读取；
不足之处：

代码实现中有些变量显得多余，部分变量命名与其功能不太匹配；

如需完整代码请给我一个一键三连，并评论：学生管理系统！我会根据大家情况发送完整代码

算了，还是发给大家吧，记得给个三连哈

#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <string>
#include <iomanip>
using namespace std;
//学科科目类
class Subject
{
	public:
		string proName;  //学科名
		double proScore; //分数
		void showCpInfo()
		{
			cout << left << setw(45) << proName;
			cout << left << setw(6) <<  proScore << endl;
		}
		//输出属性名，只显示总积分
		static void showHeader()
		{
			cout << left << setw(45) << "科目";
			cout << left << setw(6) <<  "分数" <<endl;
		}
};
//学生类
class Student
{
	public:
		string stuNum;         //学号
		string stuName;        //姓名
		string gender;         //性别
		int gradeNum;          //年级
		string department;     //专业
		int classNum;          //班级
		vector<Subject> cps;  //学生的各个科目
		int cpNum;            //科目门数
		double score;         //平均分
		Student()
		{
		}
		Student(string stuNum, string stuName, string gender, int gradeNum, string department, int classNum,vector<Subject> cps, int cpNum, double score)
		{
			this->stuNum = stuNum;
			this->stuName = stuName;
			this->gender = gender;
			this->gradeNum = gradeNum;
			this->department = department;
			this->classNum = classNum;
			this->cps = cps;
			this->cpNum = cpNum;
			this->score = score;
		}
		~Student()
		{
		}
		//输出属性值  score是平均分
		void showStuInfo()
		{
			cout << left << setw(12) << stuNum;
			cout << left << setw(10) <<  stuName;
			cout << left << setw(6) << gender;
			cout << left << setw(8) << gradeNum;
			cout << left << setw(23) << department;
			cout << left << setw(6) << classNum;
			cout << left << setw(6) << score << endl;
		}
		//输出属性名
		static void showHeader()
		{
			cout << left << setw(12) << "学号";
			cout << left << setw(10) <<  "姓名";
			cout << left << setw(6) << "性别";
			cout << left << setw(8) << "年级";
			cout << left << setw(23) << "专业";
			cout << left << setw(6) << "班级";
			cout << left << setw(6) << "平均分" << endl;
		}
};
//学生列表类
class StudentList
{
	private:
		vector<Student> stuList;
	public:
		StudentList()
		{
		}
		StudentList(vector<Student> stuList)
		{
			this->stuList = stuList;
		}
		~StudentList()
		{
		}
		//初始化
		void init()
		{
			readFile(); //读取文件
		}
		//主菜单
		void menu()
		{
			string sel = "0";
			system("cls");
			cout << "\t\t\t**********欢迎来到学生成绩管理系统**********" << endl;
			cout << "\t\t\t你可以进行以下操作:" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             1   添加学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             2   删除学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             3   修改学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             4   查询学生信息             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             5   显示信息列表             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             6   统计学生数据             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             7   清空系统数据             |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t|             0   退出                     |" << endl;
			cout << "\t\t\t|------------------------------------------|" << endl;
			cout << "\t\t\t请选择【0-7】：";
			cin >> sel;
			while(sel != "0" && sel != "1" && sel != "2" && sel != "3" && sel != "4" && sel != "5" && sel != "6" && sel != "7")
			{
				cout << "\t\t\t输入不合法,请重新选择【0-7】：";
				cin >> sel;
			}
			if(sel == "1")
			{
				this->insertList();
				this->menu();
			}
			else if(sel == "2")
			{
				this->deleteList();
				this->menu();
			}
			else if(sel == "3")
			{
				this->updateList();
				this->menu();
			}
			else if(sel == "4")
			{
				this->selectList();
				this->menu();
			}
			else if(sel == "5")
			{
				this->displayList();
				this->menu();
			}
			else if(sel == "6")
			{
				this->statisticList();
				this->menu();
			}
			else if(sel == "7")
			{
				this->clearList();
				this->menu();
			}
			else if(sel == "0")
			{
				exit(0);
			}
		}
		//读取文件
		void readFile()
		{
			ifstream ifs;
			ifs.open("stuList.txt", ios::in);
			int n = 0; //用来接收学生数量的值
			ifs >> n;
			for(int i = 0; i < n; i++)
			{
				Student s;
				ifs >> s.stuNum >> s.stuName >> s.gender >> s.gradeNum >> s.department >> s.classNum >> s.cpNum >> s.score;
				for(int j = 0; j < s.cpNum; j++)
				{
					Subject cp;
					ifs >> cp.proName >> cp.proScore;
					s.cps.push_back(cp);
				}
				stuList.push_back(s);
			}
			ifs.close();
		}
		//写入文件
		void writeFile()
		{
			ofstream ofs;
			ofs.open("stuList.txt", ios::out);
			ofs << stuList.size() << endl; //先写入学生数量
			for (int i = 0; i < stuList.size(); i++)
			{
				ofs << stuList[i].stuNum << " " <<  stuList[i].stuName << " " << stuList[i].gender
				    << " " << stuList[i].gradeNum << " " << stuList[i].department << " " << stuList[i].classNum
				    << " " << stuList[i].cpNum << " " << stuList[i].score << endl;
				for(int j = 0; j < stuList[i].cps.size(); j++)
				{
					ofs << stuList[i].cps[j].proName << " " << stuList[i].cps[j].proScore << endl;
				}
			}
			ofs.close();
		}
		//添加学生信息
		void insertList()
		{
			while(true)
			{
				system("cls");
				cout << "\t\t**********************欢迎来到添加学生信息功能*************************" << endl;
				cout<< "\t\t学生基本信息一览表："<<endl;
				displayStu();
				cout<<endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t1 添加学生信息" << endl;
				cout << "\t\t2 返回主菜单" << endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t请选择【1-2】：";
				string sel;
				cin >> sel;
				while(sel != "1" && sel != "2")
				{
					cout << "\t\t输入不合法,请重新输入【1-2】：";
					cin >> sel;
				}
				if(sel == "1")
				{
					string flag = "1";
					while (flag == "1")
					{
						cout << "\t\t输入学生信息："<<endl;
						cout << "\t\t学号：";
						Student s;
						bool check = false;
						do
						{
							check = false;
							cin >> s.stuNum;
							for(int i = 0; i < stuList.size(); ++i)
							{
								if(s.stuNum == stuList[i].stuNum)
								{
									cout<<"\t\t该学号已存在，请重新输入：";
									check = true;
									break;
								}
							}
						}
						while(check);
						cout << "\t\t姓名：";
						cin >> s.stuName;
						cout << "\t\t性别：";
						cin >> s.gender;
						cout << "\t\t年级：";
						cin >> s.gradeNum;
						cout<<"\t\t专业：";
						cin >> s.department;
						cout<<"\t\t班级：";
						cin >> s.classNum;
						s.score = 0;
						string option = "1";
						cout<<"\t\t是否添加成绩信息？（1 是 0 否）"<<endl;
						cout << "\t\t请进行选择【0-1】：";
						cin >> option;
						while(option != "0" && option != "1")
						{
							cout << "\t\t输入不合法,请重新选择【0-1】：";
							cin >> option;
						}
						if(option == "1")
						{
							int cnt = 0;
							while(option == "1")
							{
								cnt++;
								Subject cp;
								cout<<"\t\t第"<<cnt<<"科科目名称：";
								cin>>cp.proName;
								cout<<"\t\t第"<<cnt<<"科科目成绩：";
								cin>>cp.proScore;
								s.cps.push_back(cp);
								cout << "\t\t该科成绩信息添加成功！是否继续添加？（1 是 0 否）" << endl;
								cout << "\t\t请进行选择【0-1】：";
								cin >> option;
								while(option != "0" && option != "1")
								{
									cout << "\t\t输入不合法,请重新选择【0-1】：";
									cin >> option;
								}
							}
						}
						for(int i = 0; i < s.cps.size(); i++)
						{
							s.score += s.cps[i].proScore;
						}
						if(s.cps.size() > 0) s.score /= s.cps.size(); //计算平均分
						s.cpNum = s.cps.size();
						stuList.push_back(s);
						writeFile();
						cout << "\n\t\t该名学生信息添加成功！是否继续添加？（1 是 0 否）" << endl;
						cout << "\t\t请进行选择【0-1】：";
						cin >> flag;
						while(flag != "0" && flag != "1")
						{
							cout << "\t\t输入不合法,请重新选择【0-1】：";
							cin >> flag;
						}
					}
					cout << "\t\t";
					system("pause");
				}
				else
				{
					break;
				}
			}
		}
		//删除学生信息
		void deleteList()
		{
			while (true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到删除学生信息功能***********************" << endl;
				string sel = "0";
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 按学号删除" << endl;
				cout << "\t\t2 按姓名删除" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}
				if (sel == "1")
				{
					string keyNum;
					bool flag = false;
					cout << "\t\t请输入待删除学生的学号：";
					cin >> keyNum;
					for (vector<Student>::iterator it = stuList.begin(); it != stuList.end(); ++it)
					{
						if (it->stuNum == keyNum)
						{
							flag = true;
							cout << "\t\t待删除学生的信息如下：" << endl;
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							Student::showHeader();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							it->showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout << "\t\t确认删除？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}
							if (ch == "0") break;
							else
							{
								stuList.erase(it);
								writeFile();
								cout << "\t\t删除成功！" << endl;
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法删除！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else if (sel == "2")
				{
					string keyName;
					bool flag = false;
					cout << "\t\t请输入待删除学生的姓名：";
					cin >> keyName;
					for (vector<Student>::iterator it = stuList.begin(); it != stuList.end(); ++it)
					{
						if (it->stuName == keyName)
						{
							flag = true;
							cout << "\t\t待删除学生的信息如下：" << endl;
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t\t";
							Student::showHeader();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							it->showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout << "\t\t确认删除？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}
							if (ch == "0") break;
							else
							{
								stuList.erase(it);
								writeFile();
								cout << "\t\t删除成功！" << endl;
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法删除！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else
				{
					break;
				}
			}
		}
		//修改学生信息
		void updateList()
		{
			while(true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到修改学生信息功能***********************" << endl;
				string sel = "0";
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 修改学生基本信息" << endl;
				cout << "\t\t2 修改学生成绩信息" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}

				if(sel == "1")
				{
					bool flag = false;
					string keyNum;
					cout << "\t\t请输入待修改学生的学号：";
					cin >> keyNum;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuNum == keyNum)
						{
							flag = true;
							cout << "\t\t待修改学生基本信息如下：" << endl;
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							Student::showHeader();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<"\t\t";
							stuList[i].showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							
							Student s = stuList[i];
							cout << "\t\t请输入修改后的学号：";
							bool check = false;
							do
							{
								check = false;
								cin >> s.stuNum;
								for(int j = 0; j < stuList.size(); ++j)
								{
									if(s.stuNum == stuList[j].stuNum && i != j)
									{
										cout<<"\t\t该学号已被录入，请重新输入学号：";
										check = true;
										break;
									}
								}
							}
							while(check);
							cout << "\t\t请输入修改后的姓名：";
							cin >> s.stuName;
							cout << "\t\t请输入修改后的性别：";
							cin >> s.gender;
							cout << "\t\t请输入修改后的年级：";
							cin >> s.gradeNum;
							cout<<"\t\t请输入修改后的专业：";
							cin >> s.department;
							cout<<"\t\t请输入修改后的班级：";
							cin >> s.classNum;
							cout << "\t\t是否确认修改？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}

							if (ch == "0") break;
							else
							{
								stuList[i] = s;
								cout << "\t\t修改成功！" << endl;
								writeFile();
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法修改！\n" << endl;
				}
				else if(sel == "2")
				{
					bool flag = false;
					string keyNum;
					cout << "\t\t请输入待修改学生的学号：";
					cin >> keyNum;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuNum == keyNum)
						{
							flag = true;
							cout << "\t\t待修改学生成绩信息如下：" << endl;
							cout << "\t\t----------------------------------------------------------" << endl;
							cout<<"\t\t";
							cout << left << setw(8) <<  "编号";
							Subject::showHeader();
							cout << "\t\t----------------------------------------------------------" << endl;
							for(int j = 0; j < stuList[i].cps.size(); j++)
							{
								cout<<"\t\t";
								cout << left << setw(8) << j + 1;
								stuList[i].cps[j].showCpInfo();
							}
							cout << "\t\t----------------------------------------------------------" << endl;
							Student s = stuList[i];
							cout << "\t\t请选择修改方式："<<endl;
							string option = "1";
							cout << "\t\t-------------------------------" << endl;
							cout << "\t\t1 基于该学生原有成绩信息进行修改" << endl;
							cout << "\t\t2 清空该学生所有科目及成绩信息" << endl;
							cout << "\t\t-------------------------------" << endl;
							cout << "\t\t请进行选择【1-2】：";
							cin >> option;
							while(option != "1" && option != "2")
							{
								cout << "\t\t输入不合法,请重新选择【1-2】：";
								cin >> option;
							}
							Subject cp;
							if(option == "1")
							{
								s.cps.clear();
								s.score = 0;
								s.cpNum = 0;
								cout<<"\t\t输入修改后的学科成绩信息："<<endl;
								int cnt = 0;
								while(option == "1")
								{
									cnt++;
									cout<<"\t\t第"<<cnt<<"科科目名称：";
									cin>>cp.proName;
									cout<<"\t\t第"<<cnt<<"科科目成绩：";
									cin>>cp.proScore;
									s.cps.push_back(cp);
									cout << "\n\t\t添加成功！是否继续添加？（1 是 0 否）" << endl;
									cout << "\t\t请进行选择【0-1】：";
									cin >> option;
									while(option != "0" && option != "1")
									{
										cout << "\t\t输入不合法,请重新选择【0-1】：";
										cin >> option;
									}
								}
							}
							else if(option == "2")
							{
								s.cps.clear();
								s.score = 0;
								s.cpNum = 0;
							}
							//计算平均分
							for(int i = 0; i < s.cps.size(); i++)
							{
								s.score += s.cps[i].proScore;
							}
							if(s.cps.size() > 0) s.cpNum = s.cps.size();
							cout << "\t\t是否确认修改？（1 是 0 否）" << endl;
							cout << "\t\t请进行选择【0-1】：";
							string ch = "0";
							cin >> ch;
							while(ch != "0" && ch != "1")
							{
								cout << "\t\t输入不合法,请重新选择【0-1】：";
								cin >> ch;
							}
							if (ch == "0") break;
							else
							{
								stuList[i] = s;
								cout << "\t\t修改成功！" << endl;
								writeFile();
								break;
							}
						}
					}
					if (!flag) cout << "\t\t查无此人，无法修改！\n" << endl;
				}
				else
				{
					break;
				}
				cout << "\t\t";
				system("pause");
			}
		}
		//查询学生信息
		void selectList()
		{
			while (true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到查询学生信息功能************************" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 按学号查询" << endl;
				cout << "\t\t2 按姓名查询" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				string sel = "0";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}
				if (sel == "1")
				{
					string keyNum;
					bool flag = false;
					cout << "\t\t请输入待查询学生的学号：";
					cin >> keyNum;
					cout << "\t\t查询结果如下：" << endl;
					cout<<"\t\t基本信息："<<endl;
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					cout<<"\t\t";
					Student::showHeader();
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuNum == keyNum)
						{
							flag = true;
							cout<<"\t\t";
							stuList[i].showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<endl;
							cout<<"\t\t"<<stuList[i].stuName<<"成绩信息："<<endl;
							cout << "\t\t----------------------------------------------------------" << endl;
							cout<<"\t\t";
							cout << left << setw(8) <<  "编号";
							Subject::showHeader();
							cout << "\t\t----------------------------------------------------------" << endl;
							for(int j = 0; j < stuList[i].cps.size(); j++)
							{
								cout<<"\t\t";
								cout << left << setw(8) << j + 1;
								stuList[i].cps[j].showCpInfo();
							}
							cout << "\t\t----------------------------------------------------------" << endl;
							break;
						}
					}
					if (!flag) cout << "\t\t查无此人！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else if (sel == "2")
				{
					string keyName;
					bool flag = false;
					cout << "\t\t请输入待查询联系人的姓名：";
					cin >> keyName;
					cout << "\t\t查询结果如下：" << endl;
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					cout<<"\t\t";
					Student::showHeader();
					cout << "\t\t-----------------------------------------------------------------------" << endl;
					for (int i = 0; i < stuList.size(); i++)
					{
						if (stuList[i].stuName == keyName)
						{
							flag = true;
							cout<<"\t\t";
							stuList[i].showStuInfo();
							cout << "\t\t-----------------------------------------------------------------------" << endl;
							cout<<endl;
							cout<<"\t\t"<<stuList[i].stuName<<"成绩信息："<<endl;
							cout << "\t\t----------------------------------------------------------" << endl;
							cout<<"\t\t";
							cout << left << setw(8) <<  "编号";
							Subject::showHeader();
							cout << "\t\t----------------------------------------------------------" << endl;
							for(int j = 0; j < stuList[i].cps.size(); j++)
							{
								cout<<"\t\t";
								cout << left << setw(8) << j + 1;
								stuList[i].cps[j].showCpInfo();
							}
							cout << "\t\t----------------------------------------------------------" << endl;
							break;
						}
					}
					if (!flag) cout << "\t\t查无此人！\n" << endl;
					cout << "\t\t";
					system("pause");
				}
				else 
				{
					break; 
				}
			}
		}
		//遍历学生列表
		void displayStu()
		{
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			cout<<"\t\t";
			Student::showHeader();
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			for (int i = 0; i < stuList.size(); i++)
			{
				cout << "\t\t";
				stuList[i].showStuInfo();
			}
			cout << "\t\t-----------------------------------------------------------------------" << endl;
		}
		//查询获奖信息
		void displayCp()
		{
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			cout<<"\t\t";
			cout << left << setw(12) << "学号";
			cout << left << setw(10) <<  "姓名";
			Subject::showHeader();
			cout << "\t\t-----------------------------------------------------------------------" << endl;
			for (int i = 0; i < stuList.size(); i++)
			{
				for(int j = 0; j < stuList[i].cps.size(); j++)
				{
					cout << "\t\t";
					cout << left << setw(12) << stuList[i].stuNum;
					cout << left << setw(10) <<  stuList[i].stuName;
					stuList[i].cps[j].showCpInfo();
				}
			}
			cout << "\t\t-----------------------------------------------------------------------" << endl;
		}

		//显示信息列表
		void displayList()
		{
			system("cls");
			cout << "\t\t***********************欢迎来到显示信息列表功能************************" << endl;
			cout << "\t\t表1：学生基本信息一览表"<<endl;
			this->displayStu();
			cout << "\n\t\t表2：学生成绩信息一览表"<<endl;
			this->displayCp();
			cout << "\t\t";
			system("pause");
		}
		//将学生列表按学号升序排列
		static bool cmpNum(const Student& s1,const Student& s2)
		{
			return s1.stuNum < s2.stuNum;
		}
		//将学生列表按平均分降序排列，平均分相同的再按学号升序排列
		static bool cmpscore(const Student& s1,const Student& s2)
		{
			if(s1.stuNum != s2.stuNum) return s1.score > s2.score;
			else return s1.stuNum < s2.stuNum;
		}
		//统计学生数据
		void statisticList()
		{
			while(true)
			{
				system("cls");
				cout << "\t\t***********************欢迎来到统计学生数据功能************************" << endl;
				string sel = "0";
				cout << "\t\t-----------------" << endl;
				cout << "\t\t1 按学号排序" << endl;
				cout << "\t\t2 按平均分排序" << endl;
				cout << "\t\t3 返回主菜单" << endl;
				cout << "\t\t-----------------" << endl;
				cout << "\t\t请进行选择【1-3】：";
				cin >> sel;
				while(sel != "1" && sel != "2" && sel != "3")
				{
					cout << "\t\t输入不合法,请重新选择【1-3】：";
					cin >> sel;
				}
				if(sel == "1")
				{
					sort(stuList.begin(), stuList.end(), cmpNum);
					cout<<"\t\t按学号升序排列如下："<<endl;
					this->displayStu();
					int numMale = 0, numFemale = 0;
					for(int i = 0; i < stuList.size(); ++i)
					{
						if(stuList[i].gender == "男") numMale++;
						else if(stuList[i].gender == "女") numFemale++;
					}
					cout<<"\t\t一共 " << stuList.size() << " 人，其中男生 " << numMale << " 人，女生 " << numFemale << " 人。"<<endl;
					cout << "\t\t";
					system("pause");
				}
				else if(sel == "2")
				{
					sort(stuList.begin(), stuList.end(), cmpscore);
					cout<<"\t\t按平均分降序排列如下："<<endl;
					this->displayStu();
					vector<int> z(10);
					double totalscore = 0;
					for(int i = 0; i < stuList.size(); ++i)
					{
						totalscore += stuList[i].score;
						if(0 <= stuList[i].score && stuList[i].score < 60) z[0]++;
						else if(60 <= stuList[i].score && stuList[i].score < 70) z[1]++;
						else if(70 <= stuList[i].score && stuList[i].score < 80) z[2]++;
						else if(80 <= stuList[i].score && stuList[i].score < 90) z[3]++;
						else z[4]++;
					}
					cout<<"\t\tscore < 60 -------------- " << z[0] << " 人" << endl;
					cout<<"\t\t60 <= score < 70 --------- " << z[1] << " 人" << endl;
					cout<<"\t\t70 <= score < 80 --------- " << z[2] << " 人" << endl;
					cout<<"\t\t80 <= score < 90 --------- " << z[3] << " 人" << endl;
					cout<<"\t\tscore >= 90 ------------- " << z[4] << " 人" << endl;
					cout<<"\t\t所有学生平均分为："<<totalscore / stuList.size()<<endl;
					cout<<"\t\t"<<stuList.back().gradeNum<<"级"<<stuList.back().department<<stuList.back().classNum<<"班---";
					cout<<stuList.back().stuName<<"平均分最低，为："<<stuList.back().score<<"分"<<endl;
					cout<<"\t\t"<<stuList.front().gradeNum<<"级"<<stuList.front().department<<stuList.front().classNum<<"班---";
					cout<<stuList.front().stuName<<"平均分最高，为："<<stuList.front().score<<"分"<<endl;
					cout << "\t\t";
					system("pause");
				}
				else
				{
					break;
				}
			}
		}
		//清空系统数据
		void clearList()
		{
			while (true)
			{
				string sel = "0";
				system("cls");
				cout << "\t\t**************欢迎来到清空系统数据功能***************" << endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t1 确认清空系统数据" << endl;
				cout << "\t\t2 返回主菜单" << endl;
				cout << "\t\t------------------" << endl;
				cout << "\t\t请慎重选择【1-2】：";
				cin >> sel;
				while(sel != "1" && sel != "2")
				{
					cout << "\t\t输入不合法,请重新输入【1-2】：";
					cin >> sel;
				}
				if (sel == "1")
				{
					stuList.clear();
					cout << "\t\t清空成功！" << endl;
					cout << "\t\t";
					system("pause");
					writeFile();
				}
				else 
				{
					break;
				}
			}
		}
};

int main()
{
	StudentList stuList;
	stuList.init(); //读入文件数据初始化
	stuList.menu(); //打开主菜单
	return 0;
}

C++学生管理 lt 34 cout 算法数据结构排序算法

有关C++实现：学生管理系统（详细解析）的更多相关文章

Ruby 解析字符串 - 2
我有一个字符串input="maybe(thisis|thatwas)some((nice|ugly)(day|night)|(strange(weather|time)))"Ruby中解析该字符串的最佳方法是什么？我的意思是脚本应该能够像这样构建句子:maybethisissomeuglynightmaybethatwassomenicenightmaybethiswassomestrangetime等等，你明白了......我应该一个字符一个字符地读取字符串并构建一个带有堆栈的状态机来存储括号值以供以后计算，还是有更好的方法？也许为此目的准备了一个开箱即用的库？
ruby - i18n Assets 管理/翻译 UI - 2
我正在使用i18n从头开始构建一个多语言网络应用程序，虽然我自己可以处理一大堆yml文件，但我说的语言(非常)有限，最终我想寻求外部帮助帮助。我想知道这里是否有人在使用UI插件/gem(与django上的django-rosetta不同)来处理多个翻译器，其中一些翻译器不愿意或无法处理存储库中的100多个文件，处理语言数据。谢谢&问候，安德拉斯(如果您已经在rubyonrails-talk上遇到了这个问题，我们深表歉意) 最佳答案有一个rails3branchofthetolkgem在github上。您可以通过在Gemfi
ruby - 解析 RDFa、微数据等的最佳方式是什么，使用统一的模式/词汇(例如 schema.org)存储和显示信息 - 2
我主要使用Ruby来执行此操作，但到目前为止我的攻击计划如下:使用gemsrdf、rdf-rdfa和rdf-microdata或mida来解析给定任何URI的数据。我认为最好映射到像schema.org这样的统一模式，例如使用这个yaml文件，它试图描述数据词汇表和opengraph到schema.org之间的转换:#SchemaXtoschema.orgconversion#data-vocabularyDV:name:namestreet-address:streetAddressregion:addressRegionlocality:addressLocalityphoto:i
ruby - 用逗号、双引号和编码解析 csv - 2
我正在使用ruby1.9解析以下带有MacRoman字符的csv文件#encoding:ISO-8859-1#csv_parse.csvName,main-dialogue"Marceu","Giveittohimóhe,hiswife."我做了以下解析。require'csv'input_string=File.read("../csv_parse.rb").force_encoding("ISO-8859-1").encode("UTF-8")#=>"Name,main-dialogue\r\n\"Marceu\",\"Giveittohim\x97he,hiswife.\"\
ruby - 如何根据特征实现 FactoryGirl 的条件行为 - 2
我有一个用户工厂。我希望默认情况下确认用户。但是鉴于unconfirmed特征，我不希望它们被确认。虽然我有一个基于实现细节而不是抽象的工作实现，但我想知道如何正确地做到这一点。factory:userdoafter(:create)do|user,evaluator|#unwantedimplementationdetailshereunlessFactoryGirl.factories[:user].defined_traits.map(&:name).include?(:unconfirmed)user.confirm!endendtrait:unconfirmeddoenden
ruby-on-rails - 获取 inf-ruby 以使用 ruby 版本管理器 (rvm) - 2
我安装了ruby版本管理器，并将RVM安装的ruby实现设置为默认值，这样'哪个ruby'显示'~/.rvm/ruby-1.8.6-p383/bin/ruby'但是当我在emacs中打开inf-ruby缓冲区时，它使用安装在/usr/bin中的ruby。有没有办法让emacs像shell一样尊重ruby的路径？谢谢! 最佳答案我创建了一个emacs扩展来将rvm集成到emacs中。如果您有兴趣，可以在这里获取:http://github.com/senny/rvm.el
ruby-on-rails - 我更新了 ruby gems，现在到处都收到解析树错误和弃用警告! - 2
简而言之错误:NOTE:Gem::SourceIndex#add_specisdeprecated,useSpecification.add_spec.Itwillberemovedonorafter2011-11-01.Gem::SourceIndex#add_speccalledfrom/opt/local/lib/ruby/site_ruby/1.8/rubygems/source_index.rb:91./opt/local/lib/ruby/gems/1.8/gems/rails-2.3.8/lib/rails/gem_dependency.rb:275:in`==':und
ruby-on-rails - 事件管理员日期过滤器日期格式自定义 - 2
是否有简单的方法来更改默认ISO格式(yyyy-mm-dd)的ActiveAdmin日期过滤器显示格式？最佳答案您可以像这样为日期选择器提供额外的选项，而不是覆盖js:=f.input:my_date,as::datepicker,datepicker_options:{dateFormat:"mm/dd/yy"} 关于ruby-on-rails-事件管理员日期过滤器日期格式自定义，我们在StackOverflow上找到一个类似的问题： https://s
电脑0x0000001A蓝屏错误怎么U盘重装系统教学 - 2
　　电脑0x0000001A蓝屏错误怎么U盘重装系统教学分享。有用户电脑开机之后遇到了系统蓝屏的情况。系统蓝屏问题很多时候都是系统bug，只有通过重装系统来进行解决。那么蓝屏问题如何通过U盘重装新系统来解决呢？来看看以下的详细操作方法教学吧。　　准备工作：　　1、U盘一个（尽量使用8G以上的U盘）。　　2、一台正常联网可使用的电脑。　　3、ghost或ISO系统镜像文件（Win10系统下载_Win10专业版_windows10正式版下载-系统之家）。　　4、在本页面下载U盘启动盘制作工具：系统之家U盘启动工具。　　U盘启动盘制作步骤：　　注意：制作期间，U盘会被格式化，因此U盘中的重要文件请注
华为OD机试用Python实现 -【明明的随机数】 2023Q1A - 2
华为OD机试题本篇题目：明明的随机数题目输入描述输出描述：示例1输入输出说明代码编写思路最近更新的博客华为od2023|什么是华为od，od薪资待遇，od机试题清单华为OD机试真题大全，用Python解华为机试题|机试宝典【华为OD机试】全流程解析+经验分享,题型分享,防作弊指南华为o

C++实现：学生管理系统（详细解析）

1.题目要求

2.需求分析

3.整体设计

4.详细设计

主函数设计

学科科目类

主菜单

读取文件与写入文件

效果如下

添加学生信息

删除学生信息

修改学生信息

显示信息列表

显示学生列表

将学生列表按学号升序排列

将学生列表按平均分降序排列，平均分相同的再按学号升序排列

统计学生数据

清空系统数据

5.总结

有关C++实现：学生管理系统（详细解析）的更多相关文章

随机推荐