c++ map里使用结构体指针作为value

Question

编译时错误

hpp文件：
https://paste.ubuntu.com/p/xBZB8K6s3m/

cpp
https://paste.ubuntu.com/p/WYpRgjTFf2/

不采纳复制粘贴网络链接，答案

#include "messageBox.hpp"
#include <iostream>
//#include <string>
#include <map>
using namespace std;



messageBox::messageBox()
{
    waitNum = 1;
}

void messageBox::receive(int num)
{
    Node* cur = new Node(num);
    headmap.insert(num, cur);
    tailmap.insert(num, cur);

//找到上一个尾节点
    if(tailmap.find(num-1) != tailmap.end())
    {
        tailmap.at(num-1) -> next = cur;
        tailmap.erase(num-1);
        headmap.at(num-1)->next = cur;
        headmap.erase(num);
    }
//找到下一个头节点
    if(headmap.find(num+1) != headmap.end())
    {
        cur -> next = headmap.at(num+1);
        headmap.erase(num+1);
        cur -> next = tailmap.at(num+1);
        tailmap.erase(num+1);
    }
    if(waitNum == num)
    {
        print();
    }
}

void print()
{
    struct Node* tempnode = headmap.at(waitNum);
    headmap.erase(waitNum);
    while(tempnode != NULL)
    {
        cout << tempnode -> index << endl;
        tempnode = tempnode -> next;
        waitNum++;
    }
    tailmap.erase(--waitNum);
}

int main()
{
    messageBox msnbox;
    msnbox.receive(2);
    msnbox.receive(1);
    msnbox.receive(4);
    msnbox.receive(5);
    msnbox.receive(7);
    msnbox.receive(8);
    msnbox.receive(6);
    msnbox.receive(3);
    msnbox.receive(9);
    msnbox.receive(10);
    msnbox.receive(12);
    msnbox.receive(13);
    msnbox.receive(11);
}

#ifndef MESSAGEBOX_HPP
#define MESSAGEBOX_HPP
#include <map>
//#include <string>
using namespace std;



struct Node
{
    int index;
    Node* next;
    Node(int i)
    {
        index = i;
        next = NULL;
    }
};


class messageBox
{
private:
    map<int, Node*> headmap;
    map<int, Node*> tailmap;
    int waitNum;

public:
    messageBox();
    void receive(int num);
    void print();
};
#endif

Answer 1

两个地方导致编译不过的。
1.
headmap.insert(num, cur);
tailmap.insert(num, cur);
    --->
headmap.insert(std::pair<int,Node *>(num,cur));
tailmap.insert(std::pair<int,Node *>(num,cur));

2.
void print()
    --->
void messageBox::print()

虽然编译过了，但你的代码；

    if(tailmap.find(num-1) != tailmap.end())
    {
        tailmap.at(num-1) -> next = cur;
        tailmap.erase(num-1);
        headmap.at(num-1)->next = cur;
        headmap.erase(num);
    }
        运行时会导致越界，程序崩溃，你检查一下