C++利用链表模板类实现简易队列

#include "stdafx.h"
#include "MyQueue.h"
 
 
int main()
{
 MyQueue<int>myq ;
 int a[] = { 3,59,21,54,7 };
 for (int i = 0; i < 5; i++) {
 myq.push(a[i]);
 }
 myq.outPrint();// 打印队列
 myq.top();//弹出队首元素
 myq.pop();//打印队首元素
 myq.top();
 myq.getCount();//获取队列元素数量
 myq.top();
 myq.top();
 myq.outPrint();
 myq.top();
 myq.top();
 myq.pop();
  return 0;
}

#include <iostream>
using namespace std;
template<class T>
struct Node{
 T data;
 Node<T> * next;
};
template<class T>
class MyQueue{
private:
 Node<T>* head;//头指针
 int count;//队列元素数量
public:
 MyQueue();
 ~MyQueue();
 void outPrint();//打印队列元素
 void push(const T &e);//元素入队
 void top();// 返回队首元素
 void pop();//弹出队首元素
 int getCount();
 
};
template <class T>
MyQueue<T>::MyQueue(){
 count = 0;
 head = nullptr;
}
 
template <class T>
MyQueue<T>::~MyQueue(){
 if (head == nullptr) {
 cout << "已为空队列"<< endl;
 }
 else {
 Node<T> *temp;
 while (head!= nullptr) {
  temp = head;
  head = head->next;
  delete temp;
  count -= 1;
 }
 cout << "析构函数已完成"<< endl;
 cout << "队列元素个数为" << count << endl;
 }
}
template<class T>
int MyQueue<T>::getCount(){
 cout << "队列元素个数为： "<<count<< endl;
 return count;
}
 
template<class T>
void MyQueue<T>::push(const T&e) {//元素从链表头入队列
 if (e <=0) {
 cout << "请输入正数值" << endl; 
 return;
 }
 if (count == 0) {
 Node<T>*node = new Node<T>;//此处留意,声明新节点，不使用new初始化会报错
 node->data = e;
 node->next = nullptr;
 head = node;
 
 
 }
 else {
 Node<T>* temp = head;
 for (int i = 0; i < count - 1;i++) {
  temp = temp->next;
 }
 Node<T>* node=new Node<T>;
 temp->next=node;
 node->data = e;
 node->next = nullptr;
 }
 count++;//队列元素数量加1
}
template <class T>
void MyQueue<T>::outPrint() {
 if (head == nullptr) {
 cout << "空队列" << endl;
 }
 else {
 Node<T>* temp=head;
 cout << "队列元素为：";
 while (temp!=nullptr) {
  cout << temp->data<<" ";
  temp = temp->next;
 }
 cout << endl;
 
 }
}
template <class T>
void MyQueue<T>::top() {
 if (head == nullptr) {
 cout << "这是空队列，无队首元素。"<< endl;
 }
 else {
 Node<T>* temp;
 temp = head;
 head = head->next;
 cout << "弹出队首元素：" <<temp->data<< endl;
 delete temp;
 count -= 1;
 }
}
 
template <class T>
void MyQueue<T>::pop() {
 if (head == nullptr) {
 cout << "此为空队列，无队首元素。" << endl;
 return;
 }
 else {
 cout << "队首元素为：" << head->data << endl;
 }
}