单链表全部实现（绝对史上最完整 附例题）

#include<bits/stdc++.h>
using namespace std;
typedef struct LinkNode
{
    int data;
    LinkNode* next;
}LinkNode;
LinkNode *InitList()   //创建空的单链表
{
    LinkNode *L = (LinkNode*)malloc(sizeof(LinkNode));
    L->next = NULL;
    return L;
}
void initLinkList(LinkNode *L)//尾插法插入数据
{
    LinkNode *current = (LinkNode *)malloc(sizeof(LinkNode));
    L->next = current;
    printf("请输入结点数据（-1退出）");
    int tmp = 0;
    scanf("%d",&tmp);
    current->data=tmp;
    while (1)
    {
        scanf("%d", &tmp);
        if (tmp == -1)
        {
            break;
        }
        LinkNode *node = (LinkNode *)malloc(sizeof(LinkNode));
        node->next = NULL;
        node->data = tmp;
        current->next = node;//建立连接
        current = node;//更新
    }
}

int printLinkList(LinkNode* pHeader)//依次输出当前链表每个元素
{
    if (pHeader == NULL)
    {
        return 0;
    }
    if (pHeader->next == NULL)
    {
        printf("当前链表为空！
");
    }
    LinkNode* cur = pHeader->next;
    int num = 1;
    while (cur!=NULL)
    {
        printf("第%d个结点: %d  ", num, cur->data);
        cur = cur->next;
        num++;
    }
    cout<<'
';
    return 0;
}
int getLengthLinkList(LinkNode* pHeader)//输出链表的长度
{
    if (pHeader == NULL)
    {
        return 0;
    }
    LinkNode* cur = pHeader;
    int length = 0;
    while (cur->next != NULL)
    {
        cur = cur->next;
        length++;
    }
    return length;
}

int printLinkListnumber(LinkNode* pHeader,int n)//输出位置n的数字
{
    if (pHeader == NULL)
    {
        return 0;
    }
    if (pHeader->next == NULL)
    {
        printf("当前链表为空！
");
    }
    LinkNode* cur = pHeader->next;
    int num = 1;
    while (cur!=NULL)
    {
        if(num==n)
        {
            printf("第%d个结点: %d
", num, cur->data);
            break;
        }
        cur = cur->next;
        num++;
    }
    return 0;
}

int printLinkListvalue(LinkNode* pHeader,int val)//输出值为n的元素位置
{
    if (pHeader == NULL)
    {
        return 0;
    }
    if (pHeader->next == NULL)
    {
        printf("当前链表为空！
");
    }
    LinkNode* cur = pHeader->next;
    int num = 1;
    while (cur!=NULL)
    {
        if(cur->data==val)
        {
            printf("值为%d的元素位于第%d个节点里
", cur->data, num);
            break;
        }
        cur = cur->next;
        num++;
    }
    return 0;
}

//loc 插入到链表的第几个位置，从1开始 loc <=1 放在第一个位置 ，超过结点最后一个位置放在尾结点
int insertPositionLinkList(LinkNode* pHeader,int loc, int val)
{
    if (pHeader == NULL)
    {
        return 0;
    }
    LinkNode* cur = pHeader;
    int i = 1;
    while (cur->next!=NULL && i<loc)
    {
        i++;
        cur = cur->next;
    }
    //cur 为插入元素的前驱结点
    LinkNode* newNode = (LinkNode*)malloc(sizeof(LinkNode));
    newNode->data = val;
    newNode->next = cur->next;
    cur->next = newNode;
    return 1;
}
//删除结点
int deleteLinkList(LinkNode* pHeader,int val)
{
    if (pHeader == NULL)
    {
        return 0;
    }
    LinkNode* pre = pHeader;
    LinkNode* cur = pHeader->next;
    while (cur != NULL)
    {
        if (cur->data == val)
        {
            break;
        }
        pre = pre->next;
        cur = cur->next;
    }
    if (cur != NULL)
    {
        pre->next = cur->next;
        free(cur);
        cur = NULL;
    }
    return 1;
}
//清空链表 保留头结点
int clearLinkList(LinkNode* pHeader)
{
    if (pHeader == NULL)
    {
        return 0;
    }
    LinkNode* cur = pHeader->next;
    while (cur != NULL)
    {
        LinkNode* next = cur->next;
        free(cur);
        cur = next;
    }
    pHeader->next = NULL;
    return 1;
}
//销毁链表
int destroyLinkList(LinkNode* pHeader)
{
    if (pHeader == NULL)
    {
        return 0;
    }
    clearLinkList(pHeader);
    free(pHeader);
    return 1;
}
//删除第loc位置的元素
int delPositionLinkList(LinkNode* pHeader, int loc)
{
    if (pHeader == NULL || loc < 1)
    {
        cout<<"不可以！"<<endl;
        return 0;
    }
    LinkNode* cur = pHeader;
    int i = 1;
    while (cur->next != NULL&&i<loc)
    {
        i++;
        cur = cur->next;
    }
    //cur 为删除元素的前驱结点
    if (i == loc && cur->next!=NULL)
    {
        LinkNode* del = cur->next;
        cur->next = del->next;
        free(del);
        del = NULL;
        return 1;
    }
    return 0;
}
//链表反转
int reverseLinkList(LinkNode* pHeader)
{
    if (pHeader == NULL)
    {
        return 0;
    }
    LinkNode* pre = NULL;
    LinkNode* cur = pHeader->next;
    LinkNode* next = NULL;
    while (cur !=NULL)
    {
        //保存当前节点的下一个结点
        next = cur->next;
        //将当前节点的next域指向前一个结点
        cur->next = pre;

        //pre、cur 往后移动
        pre = cur;
        cur = next;
    }
    //循环结束 pre 指向最后一个结点，将头结点指向 它
    pHeader->next = pre;
    return 1;
}

int main()
{
    LinkNode* tmp;
    int x,y;
    int menu = 0;
        printf("-------------------菜单--------------------
");
        printf("---1、初始化链表---------------------------
");
        printf("---2、一次采用尾插法插入a、b、c、d、e元素--
");
        printf("---3、输出单链表；-------------------------
");
        printf("---4、判断单链表是否为空并输出单链表长度---
");
        printf("---5、输出单链表的第3个元素----------------
");
        printf("---6、输出元素d的位置----------------------
");
        printf("---7、在第4个元素位置上插入f元素-----------
");
        printf("---8、输出插入后的单链表-------------------
");
        printf("---9、删除单链表中的第2个元素；------------
");
        printf("---10、输出删除后的单链表；----------------
");
        printf("---11、单链表“原地”逆转，------------------
");
        printf("---12、输出逆转后的单链表；----------------
");
        printf("---0、退出---------------------------------
");
    while (1)
    {
        printf("请输入:");
        scanf("%d",&menu);
        if (menu == 0)
        {
            break;
        }
        switch (menu)
        {
        case 1:
            tmp=InitList();
            cout<<"初始化链表成功"<<endl;
            break;
        case 2:
            initLinkList(tmp);
            cout<<"成功"<<endl;
            break;
        case 3:
            printLinkList(tmp);
            break;
        case 4:
            cout<<"当前链表长度为："<<getLengthLinkList(tmp)<<endl;
            break;
        case 5:
            cout<<"请输入你要查询元素的位置";
            scanf("%d",&x);
            printLinkListnumber(tmp,x);
            break;
        case 6:
            cout<<"请输入你要查询元素的值";
            scanf("%d",&x);
            printLinkListvalue(tmp,x);
            break;
        case 7:
            cout<<"请输入你要插入的元素以及它位置";
            scanf("%d %d",&x,&y);
            insertPositionLinkList(tmp,x,y);
            break;
        case 8:
            printLinkList(tmp);
            break;
        case 9:
            cout<<"请输入你要删除元素的位置"<<endl;
            scanf("%d",&x);
            delPositionLinkList(tmp,x);
            break;
        case 10:
            printLinkList(tmp);
            break;
        case 11:
            reverseLinkList(tmp);
            break;
        case 12:
            printLinkList(tmp);
            break;
        default:
            break;
        }

    }
    return 0;
}

好像就是以前弄得作业

#include<bits/stdc++.h>
using namespace std;
typedef struct LinkNode
{
    int data;
    LinkNode* next;
} LinkNode;
LinkNode *InitList()   //创建空的单链表
{
    LinkNode *L = (LinkNode*)malloc(sizeof(LinkNode));
    L->next = NULL;
    return L;
}
void initLinkList(LinkNode *L)//尾插法插入数据
{
    LinkNode *current = (LinkNode *)malloc(sizeof(LinkNode));
    L->next = current;
    printf("请输入结点数据（-1退出）");
    int tmp = 0;
    scanf("%d",&tmp);
    current->data=tmp;
    while (scanf("%d",&tmp)&&tmp!=-1)
    {
        LinkNode *node = (LinkNode *)malloc(sizeof(LinkNode));
        node->next = NULL;
        node->data = tmp;
        current->next = node;//建立连接
        current = node;//更新
    }
}

int printLinkList(LinkNode* pHeader,int x)//依次输出当前链表每个元素
{
    if (pHeader == NULL)
    {
        return 0;
    }
    if (pHeader->next == NULL)
    {
        printf("当前链表为空！
");
    }
    LinkNode* cur = pHeader->next;
    cout<<"当前链表("<<x<<")存放的元素依次为："<<endl;
    while (cur!=NULL)
    {
        cout<<cur->data<<' ';
        cur = cur->next;
    }
    cout<<'
';
    return 0;
}
void Union(LinkNode *a,LinkNode *b,LinkNode *c)
{
    LinkNode *current = (LinkNode *)malloc(sizeof(LinkNode));
    c->next = current;
    LinkNode *pa = a->next;
    current->data=pa->data;
    pa=pa->next;
    while (pa!=NULL)
    {
        LinkNode *node = (LinkNode *)malloc(sizeof(LinkNode));
        node->next = NULL;
        node->data = pa->data;
        pa=pa->next;
        current->next = node;//建立连接
        current = node;//更新
    }
    LinkNode *pb = b->next;
    while(pb!=NULL)
    {
        pa=c->next;
        while(pa!=NULL)
        {
            if(pb->data==pa->data)
            {
                break;
            }
            pa=pa->next;
        }
        if(pa==NULL)
        {
            LinkNode *node = (LinkNode *)malloc(sizeof(LinkNode));
            node->next = NULL;
            node->data = pb->data;
            current->next = node;//建立连接
            current = node;
        }
        pb=pb->next;
    }
}
void Intersection(LinkNode *a,LinkNode *b,LinkNode *c)
{
    LinkNode *current = (LinkNode *)malloc(sizeof(LinkNode));
    c->next = current;
    LinkNode *pa;
    LinkNode *pb = b->next;
    bool flag=0;
    while(pb!=NULL)
    {
        pa=a->next;
        while(pa!=NULL)
        {
            if(pb->data==pa->data)
            {
                if(flag==0)
                {
                    current->data=pb->data;
                    flag=1;
                }
                else
                {
                    LinkNode *node = (LinkNode *)malloc(sizeof(LinkNode));
                    node->next = NULL;
                    node->data = pb->data;
                    current->next = node;//建立连接
                    current = node;
                }
            }
            pa=pa->next;
        }
        pb=pb->next;
    }
}
void destroyLinkList(LinkNode* L)
{
    LinkNode *pre,*p;
    pre=L;//头节点
    p=L->next;
    free(pre);
    while(p!=NULL)
    {
        pre=p;
        p=p->next;
        free(pre);
    }
    free(p);
}
int main()
{
    LinkNode* tmp1,*tmp2,*tmp3;
    int x,y;
    int menu = 0;
    printf("-------------------菜单----------------------
");
    printf("---1、初始化链表(1)--------------------------
");
    printf("---2、一次采用尾插法插入元素并输出单链表(1)--
");
    printf("---3、初始化链表(2)--------------------------
");
    printf("---4、一次采用尾插法插入元素并输出单链表(2)--
");
    printf("---5、求单链表a、b的并集并输出最终的结果---
");
    printf("---6、求单链表a、b的交集并输出最终的结果---
");
    printf("---0、退出---------------------------------
");
    while (1)
    {
        printf("请输入:");
        scanf("%d",&menu);
        if (menu == 0)
        {
            break;
        }
        switch (menu)
        {
        case 1:
            tmp1=InitList();
            cout<<"初始化链表(1)成功"<<endl;
            break;
        case 2:
            initLinkList(tmp1);
            cout<<"成功"<<endl;
            printLinkList(tmp1,1);
            break;
        case 3:
            tmp2=InitList();
            cout<<"初始化链表(2)成功"<<endl;
            break;
        case 4:
            initLinkList(tmp2);
            cout<<"成功"<<endl;
            printLinkList(tmp2,2);
            break;
        case 5:
            tmp3=InitList();
            Union(tmp1,tmp2,tmp3);
            printLinkList(tmp3,3);
            destroyLinkList(tmp3);
            break;
        case 6:
            tmp3=InitList();
            Intersection(tmp1,tmp2,tmp3);
            printLinkList(tmp3,3);
            destroyLinkList(tmp3);
            break;
        default:
            break;
        }

    }
    return 0;
}

 题目：

又回到最初的起点

class Solution {
public:
    ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
        ListNode* head=new ListNode(-1);//存放结果的链表
        ListNode* h=head;//移动指针
        int sum=0;//每个位的加和结果
        bool carry=false;//进位标志
        while(l1!=NULL||l2!=NULL)
        {
            sum=0;
            if(l1!=NULL)
            {
                sum+=l1->val;
                l1=l1->next;
            }
            if(l2!=NULL)
            {
                sum+=l2->val;
                l2=l2->next;
            }
            if(carry)
                sum++;
            h->next=new ListNode(sum%10);
            h=h->next;
            carry=sum>=10?true:false;
        }
        if(carry)
        {
            h->next=new ListNode(1);
        }
        return head->next;
    }
};