程序不显示链表，但在 c 中创建链表

Question

我是弱链表，所以请帮助我:

我的LinkedList没有在屏幕上显示(显示功能不正常)，即使链表正在成功创建，如果我使用node *head作为指向结构的全局指针，并且如果我用head(这是node *head的地址)和LinkedList *list(在函数参数中)与node *head替换list->head，然后它打印整个列表，但如果我使用list->head或list代替head(这是node *head的地址)，并根据node *head声明LinkedList *list，那么它将在链表中输入值，但不显示链表。

导致问题的代码如下:

#include<stdio.h>
#include<malloc.h>
typedef struct node{
    int data;
    struct node *next;
}node;
typedef struct LinkedList_
 {
   node *head;
 } LinkedList;

 void create( LinkedList *list ){
     char choice='y';
     do{
        node *newnode,*temp;
        newnode=(node*)malloc(sizeof(node*));
        printf("nenter the data: ");
        scanf("%d",&newnode->data);
        newnode->next=NULL;
        if(list==NULL){
            list->head=newnode;
            temp=newnode;
        }
        else{
            temp=list->head;
            while(temp->next!=NULL){
                temp=temp->next;
            }
            temp->next=newnode;
        }
        printf("ndo you want to continue(y or no)?  ");
        choice=getche();
        }while(choice=='y');
 }

 void display( LinkedList *list ){
     printf("n[");
     while(list->head!=NULL){
          printf("%d,",list->head->data);
          list->head=list->head->next;
     }
     printf("]");
 }

void main(){
     LinkedList *head=NULL;
     create(head);
     display(head);
}

Answer 1

修复如下

#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
typedef struct node{
    int data;
    struct node *next;
}node;
typedef struct LinkedList_ {
    node *head;
} LinkedList;
 void create( LinkedList *list ){
    char choice='y';
    if(!list || list->head){//guard
        fprintf(stderr, "Invalid call %s.n", __func__);
        return;
    }
    node *temp;
    do{
        node *newnode;
        newnode = malloc(sizeof(*newnode));//or malloc(sizeof(node));
        printf("nenter the data: ");
        scanf("%d", &newnode->data);
        newnode->next = NULL;
        if(list->head == NULL){
            list->head = newnode;
            temp = newnode;
        } else {
            temp = temp->next = newnode;//There is no need to follow the link
        }
        printf("ndo you want to continue(y or no)?  ");
        choice=getche();
    }while(choice=='y');
}

 void display( LinkedList *list ){
    node *curr = list->head;//head should not be changed
    printf("n[");
    while(curr != NULL){
          printf("%d,", curr->data);
          curr = curr->next;
    }
    printf("]n");
}
int main(void){
    LinkedList head = { NULL };//requires entity
    create(&head);
    display(&head);
}