簡易的學生成績管理系統（C++實現）

 

最近淺顯的學習了C++的基礎知識，想來練練手，於是就用單鏈表寫了最經典的小項目，存粹學習，所以就在控制台下寫了，寫的有點簡陋，碼了大概400多行。

下面上代碼：

#include <cstdlib>
#include <iostream>
#include <string>
using namespace std;

#define null NULL

class student
{
    private:
        friend class studentMessage;
        student *next; //節點指針
        string name; //學生姓名
        int age; //年紀
        int id; //學號
        double score[3]; //三科成績
        double total; //總分
        double average; //平均成績
    public:
        student(string _name,int _age,int _id,double *_score)
        {
            name = _name;
            age = _age;
            id = _id;
            score[0] = _score[0];
            score[1] = _score[1];
            score[2] = _score[2];
            total = score[0]+score[1]+score[2];
            average = total/3;
            next = NULL;
        }
        student() //為studentMessage初始化頭結點用
        {
            name = "null";
            age = 0;
            id = 0;
            score[0]=score[1]=score[2]=0;
            total = 0;
            average = 0;
            next = NULL;
        }
        ~student(){}
        void swap(student*);
};


void student::swap(student *q)
{
    string _name;
    int _age,_id;
    double _score[3],_total,_average;
    
    _name = name;
    name = q->name;
    q->name = _name;
    
    _age = age;
    age = q->age;
    q->age = _age;
    
    _id = id;
    id = q->id;
    q->id = _id;
    
    _score[0] = score[0];
    score[0] = q->score[0];
    q->score[0] = _score[0];
    
    _score[1] = score[1];
    score[1] = q->score[1];
    q->score[1] = _score[1];
    
    _score[2] = score[2];
    score[2] = q->score[2];
    q->score[2] = _score[2];
    
    _total = total;
    total = q->total;
    q->total = _total;
    
    _average = average;
    average = q->average;
    q->average = _average;
}






class studentMessage
{
    private:
      student *first; //頭指針
      int num; //信息中的學生人數
    public:
        studentMessage()
        {
            num = 0; //初始化學生人數為0
            first = new student;  //初始化頭結點
        }
        ~studentMessage(){delete first;}

        /*管理系統常規操作*/
        void Insret(void); //插入
        void Display(void); //顯示
        void Delete(void); //刪除
        void Search(void); //搜索
        void Change(void); //改動
        void sortByLesson1(void); //按成績一來排序
        void sortByLesson2(void); //按成績二來排序
        void sortByLesson3(void); //按成績三來排序
        void sortByTotal(void); //按總分來排序
        void SearchByid(void); //按照學號查找
        void SearchByname(void); //按照姓名查找
        int menu(void); //初始的菜單
        void clear(void); //清空列表
};


int studentMessage::menu(void)
{
    int ch;
    cout<<"**********************************************************************"<<endl;
    cout<<"======================================================================"<<endl;
    cout<<"***************************學生成績管理系統***************************"<<endl;cout<<endl;
    cout<<"1.顯示所有學生成績"<<endl;
    cout<<"2.添加學生信息"<<endl;
    cout<<"3.查詢學生信息"<<endl;
    cout<<"4.修改學生信息"<<endl;
    cout<<"5.刪除最下面一個學生信息"<<endl;
    cout<<"6.刪除所有信息"<<endl;
    cout<<"0.退出系統"<<endl;cout<<endl;
    cout<<"********************Copyright@ By Jeaven Wong**************************"<<endl;
    cout<<"======================================================================="<<endl;
    cout<<"***********************************************************************"<<endl;
    cin >> ch;
    cout<<"\n\n\n"<<endl;
    return ch;
}



//插入
void studentMessage::Insret(void)
{
    string name;
    int age;
    int id;
    double score[3];
    cout<<"請輸入學生姓名: ";
    cin>>name;
    cout<<"請輸入學生年齡: ";
    cin>>age;
    cout<<"請輸入學生學號: ";
    cin>>id;
    cout<<"下面請輸入學生三門課程成績: ";
    cout<<endl;
    cout<<"請輸入第一門課的成績: ";cin>>score[0];
    cout<<"請輸入第二門課的成績: ";cin>>score[1];
    cout<<"請輸入第三門課的成績: ";cin>>score[2];
    cout<<endl;

    
    student *newstu = new student(name,age,id,score);
    student *p = first;
    while(p->next != NULL)
    {
        p = p->next;
    }
    p->next = newstu;
    newstu->next = null;
    num++;
}



void studentMessage::Display(void)
{
    if(num == 0)
    {
        cout<<"當前記錄中無學生..."<<endl;
    }
        
    else
    {
        student *p = first->next;
        while(p != null)
        {
            cout<<"姓名:"<<p->name<<"  ";
            cout<<"年齡:"<<p->age<<"  ";
            cout<<"學號:"<<p->id<<"  ";
            cout<<"三門課程成績: "<<p->score[0]<<" "<<p->score[1]<<" "<<p->score[2]<<"  ";
            cout<<"總分:"<<p->total<<"  ";
            cout<<"平均分:"<<p->average<<endl;
            p = p->next;
        }
    }    
}


void studentMessage::Delete(void)
{
    student *p = first;
    student *pre = first;
    while(p->next != NULL)
    {
        pre = p;
        p = p->next;
    }
    pre->next = NULL;
    delete p;
    num--;
}


void studentMessage::Search(void)
{
    int temp = 0;
    cout<<"請輸入查找的條件，有如下選項..."<<endl;
    cout<<"按照學號查找（請輸入【1】） 按照姓名查找（請輸入【2】）"<<endl;
    cin>>temp;
    switch(temp)
    {
        case 1: SearchByid(); break;
        case 2: SearchByname(); break;
        default: cout<<"輸入有誤..."<<endl;
    }
}

void studentMessage::SearchByid(void)
{
    int _id;
    int flag = 0;
    cout<<"請輸入待查找學生的學號：";
    cin >> _id;
    student *p = first->next;
    while(p != null)
    {
        if(p->id == _id)
        {
            flag = 1;
            cout<<"下面是查找匹配結果："<<endl;
            cout<<"姓名:"<<p->name<<"  ";
            cout<<"年齡:"<<p->age<<"  ";
            cout<<"學號:"<<p->id<<"  ";
            cout<<"三門課程成績: "<<p->score[0]<<" "<<p->score[1]<<" "<<p->score[2]<<"  ";
            cout<<"總分:"<<p->total<<"  ";
            cout<<"平均分:"<<p->average<<endl;    
        } 
        p = p->next;
    }
    if(flag == 0)
    {
        cout<<"抱歉，記錄中沒有查找匹配項..."<<endl;
    }
}

void studentMessage::SearchByname(void)
{
    string _name;
    int flag = 0;
    cout<<"請輸入待查找的學生姓名: ";
    cin >> _name;
    student *p = first->next;
    while(p != null)
    {
        if(p->name == _name)
        {
            flag = 1;
            cout<<"下面是查找匹配結果："<<endl;
            cout<<"姓名:"<<p->name<<"  ";
            cout<<"年齡:"<<p->age<<"  ";
            cout<<"學號:"<<p->id<<"  ";
            cout<<"三門課程成績: "<<p->score[0]<<" "<<p->score[1]<<" "<<p->score[2]<<"  ";
            cout<<"總分:"<<p->total<<"  ";
            cout<<"平均分:"<<p->average<<endl;    
        }
        p = p->next;
    }
    
    if(flag == 0)
    {
        cout<<"抱歉，記錄中沒有查找匹配項..."<<endl;
    }
}



void studentMessage::Change(void)
{
    string _name;
    int flag = 0,temp;
    int _id,_age;
    int course = 0;
    cout<<"請輸入需要改動信息的學生的姓名: ";
    cin >> _name;
    student *p = first->next;
    while(p != null)
    {
        if(p->name == _name)
        {
            flag = 1;
            cout<<"該學生當前信息如下："<<endl;
            cout<<"姓名:"<<p->name<<"  ";
            cout<<"年齡:"<<p->age<<"  ";
            cout<<"學號:"<<p->id<<"  ";
            cout<<"三門課程成績: "<<p->score[0]<<" "<<p->score[1]<<" "<<p->score[2]<<"  ";
            cout<<"總分:"<<p->total<<"  ";
            cout<<"平均分:"<<p->average<<endl;    
            cout<<"請指明哪一項需要修改..."<<endl;
            cout<<"修改學號（輸入【1】） 修改年齡（輸入【2】）修改成績（輸入【3】）"<<endl;
            cin >> temp;
            switch(temp)
            {
                case 1: 
                    {
                        cout<<"請輸入新的學號：";cin>>_id;
                        p->id = _id;
                    }
                    break;
                case 2: 
                    {
                        cout<<"請輸入新的年齡：";cin>>_age;
                        p->age = _age;
                    }
                    break;
                case 3: 
                    {
                        cout<<"請按指示修改課程成績..."<<endl;
                        cout<<"是否需要修改第一門課程成績？（需要輸入【1】不需要輸入【0】）"<<endl;
                        cin >> course;
                        if(course == 1)
                        {
                            cout<<"請輸入修改后的第一門課的成績："; cin >> p->score[0];
                        }
                        course = 0;
                        
                        cout<<"是否需要修改第二門課程成績？（需要輸入【1】不需要輸入【0】）"<<endl;
                        cin >> course;
                        if(course == 1)
                        {
                            cout<<"請輸入修改后的第二門課的成績："; cin >> p->score[1];
                        }
                        course = 0;
                        
                        cout<<"是否需要修改第三門課程成績？（需要輸入【1】不需要輸入【0】）"<<endl;
                        cin >> course;
                        if(course == 1)
                        {
                            cout<<"請輸入修改后的第三門課的成績："; cin >> p->score[2];
                        }
                        course = 0;
                        
                        p->total = p->score[0]+p->score[1]+p->score[2];
                        p->average = p->total/3;
                        
                        cout<<"修改后的信息如下： "<<endl;
                        cout<<"姓名:"<<p->name<<"  ";
                        cout<<"年齡:"<<p->age<<"  ";
                        cout<<"學號:"<<p->id<<"  ";
                        cout<<"三門課程成績: "<<p->score[0]<<" "<<p->score[1]<<" "<<p->score[2]<<"  ";
                        cout<<"總分:"<<p->total<<"  ";
                        cout<<"平均分:"<<p->average<<endl;    
                    }
                    break;
                default:  cout<<"輸入有誤..."<<endl;
            }
        }
        p = p->next;
    }
    if(flag == 0)
        cout<<"當前記錄中沒有次學生..."<<endl;
}

/*排序我均采用冒泡排序法，均是從小到大排序*/


//按照科目一排序
void studentMessage::sortByLesson1(void) 
{
    student *p = first->next;
    while(p->next != null)
    {
        student *q = p->next;
        while(q != null)
        {
            if(p->score[0] > q->score[0])
            {
                p->swap(q);
            }
            q = q->next;
        }
        p = p->next;
    }
}

//按照科目二排序
void studentMessage::sortByLesson2(void)
{
    student *p = first->next;
    while(p->next != null)
    {
        student *q = p->next;
        while(q != null)
        {
            if(p->score[1] > q->score[1])
            {
                p->swap(q);
            }
            q = q->next;
        }
        p = p->next;
    }
}

//按照科目三排序
void studentMessage::sortByLesson3(void)
{
    student *p = first->next;
    while(p->next != null)
    {
        student *q = p->next;
        while(q != null)
        {
            if(p->score[2] > q->score[2])
            {
                p->swap(q);
            }
            q = q->next;
        }
        p = p->next;
    }
}

//按照總成績排序
void studentMessage::sortByTotal(void)
{
    student *p = first->next;
    while(p->next != null)
    {
        student *q = p->next;
        while(q != null)
        {
            if(p->total > q->total)
            {
                p->swap(q);
            }
            q = q->next;
        }
        p = p->next;
    }
}

void studentMessage::clear(void)
{
    student *p = first->next;
    while(p != null)
    {
        first->next = p->next;
        p->next = null;
        delete p;
        p = first->next;
    }
}



int main()
{
    studentMessage stulist;
    int ch;
    while(ch = stulist.menu())
    {
        switch(ch)
        {
            case 1: stulist.Display(); break;
            case 2: stulist.Insret(); break;
            case 3: stulist.Search(); break;
            case 4: stulist.Change(); break;
            case 5: stulist.Delete(); break;
            case 6: stulist.clear(); break;
            default: cout<<"請按要求輸入..."<<endl;
        }
    }
    return 0;
}

下面是程序運行的結果：

初始界面：

 

 插入信息：

連續插入后顯示：

 修改信息：

修改后結果：

 

 

如有錯誤，歡迎批評指針哈~