链表的基本操作（c++实现）

跟c语言不同点
1.结点建立方法与释放方法
2.c++类 加入了构造函数和析构函数
3.每个函数有略微改动

/*Keep on going Never give up*/
/*
    Author : Vinegar-Tree
    Lang : C++
    Blog : https://blog.csdn.net/xxxxxiao123
    Date ：2020/10/4 19:32
*/
//#pragma GCC optimize(3,"Ofast","inline")
#include<bits/stdc++.h>

//#define int long long
#define endl '\n'
#define Accepted 0
#define AK main()
#define I_can signed
using namespace std;
const int maxn =1010;
const int MaxN = 0x3f3f3f3f;
const int MinN = 0xc0c0c00c;
typedef long long ll;
const int inf=0x3f3f3f3f;
const ll mod=1e9+7;
using namespace std;

struct Node {   //单链表储存结构
    int date;
    Node* next;
};
class List{
private:
    Node* list;
public:
    List(){
        list = new Node;  //生成新结点作为其头节点
        list->date = 0;
        list->next = NULL;
    }
    ~List(){
        delete list;
    }

    void list_init(int n) {  //创建单链表   p是在链表中移动的，r是指向尾节点的
        Node* r = list;    //创建尾指针，指向头节点
        for (int i = 0; i < n; i++) {
            Node* p = new Node;   //生成新结点
            cin >> p->date;
            p->next = NULL;
            r->next = p;
            r = p;
        }
    }

    int list_find(int x) {   //查找某个值在链表中的位置
        Node* p = list->next;
        int cnt=0;
        while (p && p->date != x) p = p->next,cnt++;  //两种退出状况，一种是到了链表结尾，另一种是找到值，我们返回p就可以
        return cnt;
    }

    bool list_insert(int pos, int x) {   //在某位置插入值
        Node* p = list;
        int j = 0;
        while (p && j < pos- 1) {
            p = p->next;
            j++;
        }
        if (!p || j > pos - 1)  return false;   //如果输入位置不存在，返回false
        Node* s = new Node;
        s->date = x;    //将新结点的date赋值
        s->next = p->next;   //尾插法逻辑
        p->next = s;
        return true;   //插入成功
    }

    int list_len() {  //遍历列表求其长度
        int icount = 0;
        Node *node=list;
        while (node->next) {
            node = node->next;
            icount++;
        }
        return icount;
    }

    void list_print() {   //遍历链表输出储存值
        Node *node=list;
        node = node->next;
        while (node != NULL) {  //当链表没有走到末尾
            cout << node->date << " ";
            node = node->next;
        }
        cout << endl;
    }

    bool list_delete(int i) {  //删除某元素
        Node* p = list;
        int j = 0;
        while (p->next && j < i - 1) {
            p = p->next;
            j++;
        }
        if (!p->next || j > i - 1)  return false;
        Node* q = p->next;
        p->next = q->next;
        delete q;
        return true;
    }

    int list_searchnode(int i) {  //查询第i个结点的值
        int j = 0;
        Node *node=list;
        while (j < i && node) {  //停止条件是到达此节点或者到达链表末尾，在后面再检查是哪个原因停止下来的。
            node = node->next;
            j++;
        }
        //cout << j << endl;
        if (!node || j > i)  return -1;
        else return node->date;
    }
};

I_can AK{
    ios::sync_with_stdio(false);
    List ok;
    int n;
    cin>>n;
    ok.list_init(n);
    ok.list_print();

    if(ok.list_insert(1,99)) cout<<"成功"<<endl;
    else cout<<"插入失败"<<endl;

    ok.list_print();

    if(ok.list_delete(1)) cout<<"删除成功"<<endl;
    else cout<<"删除失败"<<endl;
    ok.list_print();

    if(ok.list_find(5))
    cout<<"第5这个值在链表中的位置"<<ok.list_find(5)+1<<endl;
    else  cout<<"未查询到此值"<<endl;


    if(ok.list_searchnode(1)!=-1)
    cout<<ok.list_searchnode(1)<<endl;
    else cout<<"此节点不存在"<<endl;


    cout<<"此链表长度为："<<ok.list_len()<<endl;

    ok.list_print();
    return Accepted;
}