要求如下：编写一个能为栈也能为队列的线性表，根据要求完善下列代码： #include <iostream> using namespace std; #include<string> #include"math.h" template<class T> class vlist//线性表抽象类 { public: virtual void in(T &e)=0; virtual T out()=0; }; template<class T> class Element//线性表存储元素 { public: T data; Element<T> next; Element(){} }; //在beign和end之间完成SStack和Quene类的定义及实现，其继承vlist /begin/ /end***/ int main() { vlist<int> *intp; vlist<string> *strp; SStack<int> ints; Quene<int> intq; SStack<string> strs; Quene<string> strq; intp=&ints; int t=2; intp->in(t); t=3; intp->in(t); t=4; intp->in(t); for(int i=0;i<3;i++) cout<<intp->out(); intp=&intq; t=2; intp->in(t); t=3; intp->in(t); t=4; intp->in(t); for(int i=0;i<3;i++) cout<<intp->out(); strp=&strs; string str; cout<<endl; for(int i=0;i<3;i++) { cin>>str; strp->in(str); } for(int i=0;i<3;i++) cout<<strp->out()<<" "; cout<<endl; strp=&strq; for(int i=0;i<3;i++) { cin>>str; strp->in(str); } for(int i=0;i<3;i++) cout<<strp->out()<<" "; }

代码如下：

#include <iostream>
#include <string>
#include <math.h>

using namespace std;

template<class T>
class vlist // 线性表抽象类
{
public:
    virtual void in(T &e) = 0;
    virtual T out() = 0;
};

template<class T>
class Element // 线性表存储元素
{
public:
    T data;
    Element<T>* next;
    Element() { next = NULL; }
};

template<class T>
class SStack : public vlist<T> // 栈的实现类
{
private:
    Element<T>* top; // 栈顶元素指针
public:
    SStack() { top = NULL; }
    void in(T &e) // 入栈操作
    {
        Element<T>* p = new Element<T>;
        p->data = e;
        p->next = top;
        top = p;
    }
    T out() // 出栈操作
    {
        if (top == NULL) // 栈空，抛出异常
            throw "Stack is empty!";
        Element<T>* p = top;
        top = top->next;
        T temp = p->data;
        delete p;
        return temp;
    }
};

template<class T>
class Quene : public vlist<T> // 队列的实现类
{
private:
    Element<T>* front; // 队头元素指针
    Element<T>* rear; // 队尾元素指针
public:
    Quene() { front = rear = NULL; }
    void in(T &e) // 入队列操作
    {
        Element<T>* p = new Element<T>;
        p->data = e;
        p->next = NULL;
        if (front == NULL)
            front = rear = p;
        else
        {
            rear->next = p;
            rear = p;
        }
    }
    T out() // 出队列操作
    {
        if (front == NULL) // 队空，抛出异常
            throw "Quene is empty!";
        Element<T>* p = front;
        front = front->next;
        T temp = p->data;
        delete p;
        return temp;
    }
};

int main() {
    vlist<int>* intp;
    vlist<string>* strp;
    SStack<int> ints;
    Quene<int> intq;
    SStack<string> strs;
    Quene<string> strq;

    intp = &ints;
    int t = 2;
    intp->in(t);
    t = 3;
    intp->in(t);
    t = 4;
    intp->in(t);
    for (int i = 0; i < 3; i++)
        cout << intp->out() << " ";

    intp = &intq;
    t = 2;
    intp->in(t);
    t = 3;
    intp->in(t);
    t = 4;
    intp->in(t);
    for (int i = 0; i < 3; i++)
        cout << intp->out() << " ";

    strp = &strs;
    string str;
    cout << endl;
    for (int i = 0; i < 3; i++) {
        cin >> str;
        strp->in(str);
    }
    for (int i = 0; i < 3; i++)
        cout << strp->out() << " ";
    cout << endl;

    strp = &strq;
    for (int i = 0; i < 3; i++) {
        cin >> str;
        strp->in(str);
    }
    for (int i = 0; i < 3; i++)
        cout << strp->out() << " ";
}

这段代码定义了一个 vlist 抽象类，并且定义了两个线性表的实现类：SStack 和 Quene，分别实现了栈和队列的基本操作。在 main 函数中，分别使用了栈和队列的实现类，演示了它们的基本操作。