建立標頭檔案LinkQueue.h

#ifndef LinkQueue_h
#define LinkQueue_h

template <class DataType>
//使用結構體定義結點
struct Node{
    DataType data;
    Node<DataType> *next;  //指向下一個結點的指標
};

template <class DataType>
class LinkQueue{
public:
    LinkQueue();  //建構函式
    ~LinkQueue();  //解構函式
    void EnQueue(DataType x);  //入隊函式
    DataType DeQueue();  //出隊函式
    DataType GetQueue();  //得到隊頭元素
    int Empty();  //判斷鏈佇列是否為空
private:
    Node<DataType> *front, *rear;
};
#endif /* LinkQueue_h */
 

建立原始檔LinkQueue.cpp實現標頭檔案中的成員函式

#include <stdio.h>
#include "LinkQueue.h"

template <class DataType>
LinkQueue<DataType>::LinkQueue(){
    Node<DataType> *s = NULL;
    s = new Node<DataType>;
    s -> next = NULL;
    front = rear = s;
}

template <class DataType>
LinkQueue<DataType>::~LinkQueue(){
    Node<DataType> *p = NULL;
    while(front != NULL){
        p = front ->next;
        delete front;
        front = p;
    }
}

template <class DataType>
void LinkQueue<DataType>:: EnQueue(DataType x){
    Node<DataType> *s = NULL;
    s = new Node<DataType>;
    s -> data = x;
    s -> next = NULL;
    rear -> next = s;
    rear = s;
}

template <class DataType>
DataType LinkQueue<DataType>:: DeQueue(){
    Node<DataType> *p = NULL;
    int x;
    if (rear == front) throw "underflow";
    p = front->next;
    x = p->data;
    front->next = p->next;
    if (p->next == NULL) rear = front;
    delete p;
    return x;
}

template <class DataType>
DataType LinkQueue<DataType>::GetQueue(){
    return front -> next -> data;
}

template <class DataType>
int LinkQueue<DataType>::Empty(){
    if (front == rear) return 1;
    else return 0;
}
 

編寫主程式

#include <stdio.h>
#include <iostream>
#include "LinkQueue.cpp"
using namespace std;

int main(){
    LinkQueue<int> Q;
    if(Q.Empty()){
        cout << "Queue is empty!" << endl;
    }
    else {
        cout << "Queue is not empty!" << endl;
    }
    
    try{
        Q.EnQueue(5);
        Q.EnQueue(10);
    }
    catch(char *wrong){
        cout << wrong << endl;
    }
    
    Q.EnQueue(5);
    Q.EnQueue(10);
    
    cout << Q.GetQueue() << endl;
    
    try{
        Q.DeQueue();
    }
    catch(char *wrong){
        cout << wrong << endl;
    }
    
    cout << Q.GetQueue() << endl;
    
    return 0;
}