期末考預告-1

#include <iostream>
using namespace std;


class node
{
public:
    int num;
    node *next=NULL;
};

class queue
{
public:
    queue(){ cout << "***head= " << head << endl; }
    void push(int);
    void pop();
private:
    node *head = new(node);
};

void queue::push(int n)
{
    node *pos=head;
    while (pos->next!=NULL)
    {
        pos = pos->next;
    }
    pos->next = new(node);
    pos->next->num = n;
    cout << "***push " << n << " to " << pos->next << endl;
}

void queue::pop()
{
    if (head->next == NULL)
    {
        cout << "empty queue!\n";
        return;
    }
    node *del=head->next;
    head->next = head->next->next;
    cout << "pop " << del->num <<" frome "<< del << endl;
    delete(del);
}


void main()
{
    cout << "new qu1\n";
    queue qu1;
    cout << "start push\n";
    qu1.push(1);
    qu1.push(2);
    qu1.push(3);
    qu1.push(4);
    cout << "start pop\n";
    qu1.pop();
    qu1.pop();
    qu1.pop();
    qu1.pop();
    qu1.pop();
}