定义一个LinkedQueue类的对象queue和一个LinkedStack类的对象stack，并根据用户的输入分别对queue和stack作出相应的操作。若为"Push",则压栈；若为"EnQueue",则入队；若为"Pop",则出栈；若为"DeQueue",则出队；若为"Exit"，则退出；若为其它，则给出提示信息"Input error!"。入栈和入队时，输入学生姓名和学号。出栈和出队时，若非空，则输出被删除的学生信息；若栈空，则输出Stack is empty!"；若队空，则输出"Queue is empty!"

我的Pop和DeQueue异常，但是不知道怎样修改

例：输入
Push
ZhangSan 200905
Push
LiSi 200906
EnQueue
WangWu 200907
Pop
exit
Exit

输出
ame: LiSi, Number: 200906
Input error!

以下是我的代码
#include <iostream>
#include <cstring>
#include <cstdlib>
#include <cstdio>
using namespace std;

static int Alternative(string situation);

class StudentRecord
{
public:
    string StuName;
    int StuNo;
    StudentRecord();
    StudentRecord(string name,int number);
    void print();
};

StudentRecord::StudentRecord()
{
    StuName="Hello";
    StuNo=2014;
}

StudentRecord::StudentRecord(string name,int number)
{
    StuName=name;
    StuNo=number;
}

void StudentRecord::print()
{
    cout<<"Name:"<<StuName<<", Number:"<<StuNo<<endl;
}

class StudentNode
{
public:
    StudentRecord data;
    StudentNode *next;
public:
    StudentNode();
    StudentNode(StudentRecord record);
    ~StudentNode();
};

StudentNode::StudentNode()
{
    this->next=NULL;
}

StudentNode::StudentNode(StudentRecord record)
{
    this->data=record;
    this->next=NULL;
}

StudentNode::~StudentNode()
{
    /*StudentNode *p,*q;
    p=next->next;
    while(p)
    {
        q=p;
        p=p->next;
        delete q;
    }*/
}

class LinkedList
{
public:
    StudentNode* HeadNode;
public:
    LinkedList();
    void PushFront(StudentNode* node);
    void PopFront();
    void PushBack(StudentNode* node);
    void PopBack();
    void AllList();
};

LinkedList::LinkedList()
{
    HeadNode=new StudentNode;
    HeadNode->next=NULL;
}

void LinkedList::PushFront(StudentNode* node)
{
    node->next=HeadNode->next;
    HeadNode->next=node;
}

void LinkedList::PopFront()
{
    StudentNode* temp=HeadNode->next;
    if(temp==NULL)
    {
        cout<<"Stack is empty!"<<endl;
    }
    else
    {
        temp->data.print();
        HeadNode->next=temp->next;
        delete temp;
    }
}

void LinkedList::PushBack(StudentNode* node)
{
    StudentNode* temp=HeadNode;
    if(temp)
    {
        while(temp->next!=NULL)
        {
            temp=temp->next;
        }
        temp->next=node;
    }
    else
    {
        HeadNode->next=node;
    }
}

void LinkedList::PopBack()
{
    StudentNode* temp=HeadNode;
    StudentNode* q=temp;
    if(temp->next==NULL)
    {
        cout<<"Queue is empty!"<<endl;
    }
    else
    {
        while(q->next)
        {
            temp=q;
            q=q->next;
        }
        q->data.print();
        temp->next=NULL;
        delete q;
    }
}

void LinkedList::AllList()
{
    StudentNode* temp=HeadNode;
    while(temp->next!=NULL)
    {
        temp->next->data.print();
        temp=temp->next;
    }
}

class LinkedStack:public LinkedList
{
public:
    void Push(StudentRecord record);
    void Pop();
};

void LinkedStack::Push(StudentRecord record)
{
    StudentNode* temp=new StudentNode;
    temp->data.StuName=record.StuName;
    temp->data.StuNo=record.StuNo;
    temp->next=NULL;
    LinkedList::PushFront(temp);
}

void LinkedStack::Pop()
{
    LinkedList::PopFront();
}

class LinkedQueue:public LinkedList
{
public:
    void EnQueue(StudentRecord record);
    void DeQueue();
};

void LinkedQueue::EnQueue(StudentRecord record)
{
    StudentNode* temp=new StudentNode;
    temp->data.StuName=record.StuName;
    temp->data.StuNo=record.StuNo;
    temp->next=NULL;
    LinkedList::PushBack(temp);
}

void LinkedQueue::DeQueue()
{
    LinkedList::PopBack();
}

static int Alternative(string situation)
{
    int Alter;
    if(situation=="Push")
    {
        Alter=1;
    }
    else if(situation=="Pop")
    {
        Alter=2;
    }
    else if(situation=="EnQueue")
    {
        Alter=3;
    }
    else if(situation=="DeQueue")
    {
        Alter=4;
    }
    else if(situation=="Exit")
    {
        Alter=5;
    }
    else
    {
        Alter=6;
    }
    return Alter;
}

int main()
{
    StudentRecord record;
    StudentNode node;
    LinkedStack stack;
    LinkedQueue queue;
    string situation;
    string name;
    int number;
    while(1)
    {
        cin>>situation;
        switch(Alternative(situation))
        {
        case 1:
            cin>>name>>number;
            record=StudentRecord(name,number);
            stack.Push(record);
            getchar();
            break;
        case 2:
            stack.Pop();
            getchar();
            break;
        case 3:
            cin>>name>>number;
            record=StudentRecord(name,number);
            queue.EnQueue(record);
            getchar();
            break;
        case 4:
            queue.DeQueue();
            getchar();
            break;
        case 5:
            exit(0);
            break;
        case 6:
            cout<<"Input error!"<<endl;
            break;
        }
    }

    return 0;
}