Question

我正在编写一个涉及类中链表的程序。添加到列表中的节点将按照＆＃34;优先级＆＃34;按升序排序。这是随机的。当添加的节点具有按升序排列的优先级时，它可以正常工作，但是当发送的优先级按降序或有些随机时，运行时错误和崩溃结果。提供的代码导致崩溃，提供示例输出，非常感谢任何帮助

Header.h

#include <iostream>
#include <string>

using namespace std;

class CCPU {
public :
    CCPU();
    ~CCPU();
    void Process();
    void AddComm(string, int);
    void PrintNodes();
    int length;
private : 
    struct NODE {
        string command;
        int priority;
        NODE *pNext;
    };

    NODE *Head;
};

Functions.cpp

#include "Header.h"

CCPU::CCPU()
{
    Head = NULL;
    length = 0;
}

CCPU::~CCPU()
{
    delete Head;
    Head = NULL;
    length = 0;
}

void CCPU::Process()
{
    if (length != 0)
    {
        Head = Head->pNext;
        cout << "Next command was processed!" << endl;
        length--;
    }
    else
        cout << "Cannot process next command; the list is empty!" << endl;
}

void CCPU::AddComm(string inCom, int inPri)
{
    NODE *pNew = new NODE,
        *pPrev = NULL,
        *pCurr = Head;
    pNew->command = inCom;
    pNew->priority = inPri;
    pNew->pNext = NULL;

    while (pCurr && inPri >= pCurr->priority)
    {
        pPrev = pCurr;
        pCurr = pCurr->pNext;
    }


    if (pPrev == NULL)
    {
        Head = pNew;
        if (length != 0)
        {
            pNew->pNext = pCurr;
        }
    }
    else
        pPrev->pNext = pNew;

    length++;
    cout << "Command \"" << inCom << "\" added, with a priority of " << inPri << endl;
}

void CCPU::PrintNodes()
{
    NODE *pCur = Head;
    while (pCur != NULL)
    {
        cout << pCur->command << endl;
        cout << pCur->priority << endl;
        cout << endl;
        pCur = pCur->pNext;
    }

    return;
}

Main.cpp的

#include "Header.h"

int main()
{
    CCPU cpu1;

    cpu1.AddComm("ADD", 4);
    cpu1.AddComm("SUB", 3); 
    cpu1.AddComm("SUB", 2);
    cpu1.AddComm("SUB", 3); 
    cpu1.Process();
    cpu1.Process(); 
    cpu1.Process(); 
    cpu1.Process();
    cpu1.PrintNodes(); 
    return 0;
}

输出： enter image description here

Answer 1

除非您尝试研究链接列表（并且肯定不是这样），否则我建议您使用std::list，std::forward_list或std::priority_queue。

您当前的代码包含很多错误。例如，在你的析构函数中，你只是通过释放头节点来泄漏内存。

Linked List Program运行时崩溃

1 个答案: