PriorityQueue的排队方法不起作用

Question

我在实施优先级队列时遇到问题。每当我执行以下代码时，文本文件中的第一项打印，但程序在此之后停止。

void loadCustomerData(){
    double simClock, avgSelectionTime;
    int items;

    ifstream myfile ("arrival.txt");
    if (myfile.is_open()){
      while ( myfile >> simClock >> items >> avgSelectionTime){

        Customer cust(simClock, items, avgSelectionTime) ;
        cout << cust << endl;
        Event e(EventType::Arrival, simClock, cust);
        events.enqueue(e);
      }
      myfile.close();
    }else
    throw(1);
}

如果我注释掉在PriorityQueue“事件”中排队的行，它们将全部打印出来。所以我认为enqueue方法存在问题。我猜它与我的节点设置方式有关，因为它之前抛出了编译错误。如果有人能告诉我哪里出错了，那将非常感激。这是我的优先级队列的代码：

#pragma once
#include <iostream>
using namespace std;

template <class T> class MyPriorityQueue
{
  private:
    struct Node{
      Node * next;
      double priority;
      T value;
      Node(T value, double priority, Node * next = NULL){
        this->next = next;
        this->value = value;
        this->priority = priority;
      }
    };
    Node *head;
  public:
    int size = 0;

    MyPriorityQueue(){
      head = NULL;
      size = 0;
    }
    ~MyPriorityQueue(){
      if(head){
        Node * lead = head->next;
        Node * follow = head;
        while(lead){
          delete(follow);
          follow = lead;
          lead = lead->next;
        }
        delete(follow);
      }
    }
    void enqueue(T item){
      Node *temp, *q;
      temp->priority = item.simTime;
      temp->value = item;
      if (head == NULL || temp->priority < head->priority){
        temp->next = head;
        head = temp;
        size ++;
      }
      else{
        q = head;
        while (q->next != NULL && q->next->priority <= temp->priority){
          q=q->next;
          temp->next = q->next;
          q->next = temp;
          size ++;
        }
      }
    }
    Event dequeue(){
      Node *temp;
      temp = head;
      head = head->next;
      return temp->value;
      free(temp);
      size --;
    }
};