链表增删改查

#include <cstdio>
#include <cstdlib>
#include <iostream>
using namespace std;
typedef struct _NPC{
    char name[20];
    int attack;
    int hp;
}NPC;
typedef struct _node{
    NPC data;
    struct _node *pNext;
}Node;
Node *head = NULL;//定义一个头节点
//添加节点
void addNode(){
    if (head == NULL) {
        //head申请一个内存空间
        head = (Node*)malloc(sizeof(Node));
        printf("请输入NPC的名字 攻击力 生命值:\n");
        scanf("%s %d %d",head->data.name,&head->data.attack,&head->data.hp);
        head->pNext=NULL;
    } else {
        Node *p = head;//指向头节点
        while (p->pNext != NULL) {
            p = p->pNext;
        }
        //申请内存空间
        p->pNext = (Node*)malloc(sizeof(Node));
        p = p->pNext;
        printf("请输入NPC的名字 攻击力 生命值:\n");
        scanf("%s %d %d",p->data.name,&p->data.attack,&p->data.hp);
        p->pNext = NULL;
    }
    printf("添加节点成功！\n");
}
//输出所有节点
void printAllNode(){
    Node *q = head;//指向头节点
    while (q!=NULL) {
        printf("名字为：%s，攻击力：%d，生命值：%d\n",q->data.name,q->data.attack,q->data.hp);
        q=q->pNext;
    }
    printf("输出所有节点成功！\n");
}
//插入节点
void insertNode(){
    //创建一个新的节点
    Node *newNode = (Node*)malloc(sizeof(Node));
    printf("请输入NPC的名字 攻击力 生命值:\n");
    scanf("%s %d %d",newNode->data.name,&newNode->data.attack,&newNode->data.hp);
    printf("请输入插入到第几个节点之后：\n");
    int num;
    scanf("%d",&num);
    Node *p = head;//指向头节点
    int count=0;//计数
    while (p != NULL) {
        count++;
        if (count == num) {
            break;
        }
        p=p->pNext;
    }
    Node *p2 = p->pNext;
    p->pNext = newNode;
    newNode->pNext = p2;
    printf("插入节点成功！\n");
}
//修改节点
void modifyNode(){
    int num;
    printf("请输入您要修改的节点：\n");
    scanf("%d",&num);
    Node *p = head;//指向头节点
    int count = 0;//计数
    while (p != NULL) {
        count++;
        if (count == num) {
            break;
        }
        p=p->pNext;
    }
    printf("请输入NPC的名字 攻击力 生命值:\n");
    scanf("%s %d %d",p->data.name,&p->data.attack,&p->data.hp);
    printf("修改节点\n");
}
//删除节点
void deleteNode(){
    int num;
    printf("请输入要删除第几个节点：\n");
    scanf("%d",&num);
    Node *p = head;//指向头节点
    int count = 0;//统计节点数
    while (p != NULL) {
        count++;
        p=p->pNext;
    }
    if (count == 1) {//删除头节点
        p=head;
        head = head->pNext;
        free(p);//将原来的节点释放掉
    }else if(count == num){//删除最后一个节点
        Node *q = head;//指向头节点
        while (q->pNext->pNext != NULL) {
            q = q->pNext;
        }
        free(q->pNext->pNext);//释放节点
        q->pNext = NULL;
    }else{
        Node *q1 = head;//指向头节点
        int n=1;//统计节点数
        while (q1 != NULL) {
            n++;
            if (n == num) {
                break;
            }
            q1 = q1->pNext;
        }
        Node * p2 = q1->pNext;
        q1->pNext = p2->pNext;//q1->pNext->pNext
        free(p2);
    }
    printf("删除节点成功！\n");
}
int main(int argc, const char * argv[]) {
    // 如何实现一个链表，当用户希望添加NPC的时候，可以在链表上增加一个NPC变量的节点,输出所有的节点，插入，修改，删除，退出系统
    printf("NPC管理系统！\n");
    int num;
    while (1) {
        printf("\n1.添加NPC节点\n");
        printf("2.输出所有NPC的节点\n");
        printf("3.插入NPC的节点\n");
        printf("4.修改NPC的节点\n");
        printf("5.删除NPC的节点\n");
        printf("6.退出系统\n");
        printf("请选择所需操作：\n");
        scanf("%d",&num);
        switch (num) {
            case 1:
                addNode();//添加节点
                break;
            case 2:
                printAllNode();//输出所有节点
                break;
            case 3:
                insertNode();//插入节点
                break;
            case 4:
                modifyNode();//修改节点
                break;
            case 5:
                deleteNode();//删除节点
                break;
            case 6:
                return 0;
                break;
            default:
                break;
        }
    }
    return 0;
}