数据结构学习中的简单问题(一)：用链表方式实现的队列输出杨辉三角

之前没怎么花时间，面临数据结构考试了，看了一天的数据结构，把链表，栈，队列都看了一遍，写点示例程序加深一下印象。

template <class T>
struct QueueNode {
    T data;
    QueueNode<T> *link;
    QueueNode(T d = 0, QueueNode<T> *next = NULL) : data(d), link(next) { }
};

template <class T>
class LinkedQueue {    
    private:
        QueueNode<T> *front, *rear;//队头、队尾指针
    public: 
        LinkedQueue() : rear(NULL), front(NULL) { }
        ~LinkedQueue();
        bool EnQueue(T x);      //x加入队列
        bool DeQueue(T& x);     //删除队头元素,x返回其值
        bool GetFront(T& x);     //查看队头元素的值    
        void MakeEmpty();      //置空队列
        bool IsEmpty() const { return front == NULL; }
        bool IsFull() const { return false; } 
};

template <class T>
LinkedQueue<T>::~LinkedQueue() {//析构函数
    QueueNode<T> *p;
    while (front != NULL) {//逐个结点释放
        p = front;  front = front->link;  delete p;
    }
};

template <class T>
bool LinkedQueue<T>::EnQueue(T x)
{
    QueueNode<T> *newNode=new QueueNode<T>(x);
    if(front==NULL){
        front=newNode;
        rear=newNode;
        if(front==NULL) return false;
    }
    else{
        rear->link=newNode;
        if (rear->link == NULL) return false;
        rear=newNode;
    }
    return true;
};

template <class T>
bool LinkedQueue<T>::DeQueue(T& x) {
    if(front==NULL) return false;
    QueueNode<T> *del=front;
    front=front->link;
    x=del->data;
    delete del;
    return true;
};

template <class T> 
bool LinkedQueue<T>::GetFront(T& x) {
    if(front==NULL) return false;
    x=front->data;
    return true;
};

主程序:

#include <iostream>
#include "LinkedQueue.h"
using namespace std;

int main()
{
    LinkedQueue<int> q;
    int n=1,t=1,u=0,s=0;
    q.EnQueue(n);
    q.EnQueue(n);
    cin>>n;//n represents the number of lines to be display
    cout<<1<<" "<<1<<endl;//Print the first line 
    for(int i=1;i<n;i++){
        s=0;q.EnQueue(s);//s saves the value that is deleted from the queue in the last round
        for(int j=0;j<i+2;j++){
            q.DeQueue(t);//t saves the value that is deleted from the queue in this round
            u=s+t;q.EnQueue(u);
            s=t;//let s=t,for the preparation of next round
            cout<<u<<" ";
        }
        cout<<endl;
    }
}