链接列表中的C字符

我试图创建一个链表，该链表将用户name, age和ssn数字作为输入，并以列表格式打印输出。我得到一些错误，所以不能得到[input?].

#include <stdio.h>
#include <stdlib.h>
struct person
{
    char *name;
    int age;
    char *ssn;
};
struct node
{
    struct person * person;
    struct node * next;
} *head, *element;
void insert (struct person *new_person)
{
    element->person = new_person;
    element->next = head;
    head = element;
}
void display (struct node *ll)
{
    if(ll == NULL)
        printf("empty list");
    while(ll != NULL)
    {
        printf("%s %d  %s ", ll->person->name, ll->person->age, ll->person->ssn);
        ll = ll->next;
        if(ll != NULL)
            printf("->");
    }
}
main()
{
    int total_no_person, i, page;
    printf("enter the total number of person t");
    scanf("%d", &total_no_person);
    struct node * temp = (struct node *) malloc(sizeof(struct node));
    struct person * new_person;
    char *pname = NULL;
    char *pssn = NULL;
    head = NULL;
    for(i = 0; i < total_no_person; i++)
    {
        pname = (char *) malloc(100);
        pssn = (char *) malloc(100);
        struct person * newly;
        printf("enter the %dth person's name t", i + 1);
        scanf("%s", &pname);
        newly[i].name = pname;
        printf("enter %dth person's age t", i + 1);
        scanf("%d", &page);
        newly[i].age = page;
        printf("enter %dth person's ssn t", i + 1);
        scanf("%s", &pssn);
        newly[i].ssn = pssn;
        new_person = newly;
        insert(new_person);
    }
    temp = head;
    display(temp);
}

有....这里有很多错误

第一个跳出来的东西:

struct person *newly;
...
newly[i].name=pname;

newly是一个person指针。你从来没有分配一个person，然后尝试访问它，就像它是一个本地结构体(多次)…一个数组?

struct person *newly = malloc(sizeof(struct person));

就是你要找的。然后将其传递给insert函数:

insert(newly);

new_person是多余的，不做任何事情。你的node

也一样

你也从来没有分配列表本身的头。你的insert假设有一个头……这里没有。您应该将element设置为NULL，并检查，因为如果它是NULL…这是第一次插入列表。(编辑:嗯，好吧，实际上head和…再读一遍，我不知道你想用element)

做什么

老实说，我建议你在谷歌上搜索一下，或者一本初学者的C书。我们可以指出代码中的所有问题，但是如果您不了解实际上使用的是什么，那么您将无法从中受益。

EDIT:话虽如此，我想发布一个工作示例是合理的，尽可能多地挽救原始代码。

#include<stdio.h>
#include<stdlib.h>
struct person
{
    char *name;
    int age;
    char *ssn;
};
/* Note: because head and tail are global they
   are initialized to NULL automatically */
struct node
{
    struct person *person;
    struct node *next;
} *head, *tail;

void insert(struct person *new_person)
{
    /* allocate a new node */
    struct node *node = malloc(sizeof(struct node));
    /* assign the person to the node */
    node->person = new_person;
    node->next = NULL;
    if (head == NULL)
    {
         /* Since head is NULL, we are inserting for the first time.
            Set the head and tail to point at our new node */
        head = node;
        tail = node;
    }
    else
    {
        /* the tail is the last node in our list. We attach the new
           node to its next, then repoint the tail to our new node */
        tail->next = node;
        tail = node;
    }
}
void display()
{
    if(head == NULL)
    {
        printf("empty listn");
    }
    else
    {
        struct node *current = head;
        while(current != NULL)
        {
            printf("%s %d  %s ", current->person->name, 
                                 current->person->age, 
                                 current->person->ssn);
            current = current->next;
            if(current != NULL)
                printf("->");
        }
        printf("n");
    }
}

main()
{
    int total_no_person,i;
    printf("enter the total number of person t");
    scanf("%d",&total_no_person);
    for(i=0;i<total_no_person;i++)
    {
        /* allocate a new person, then allocate its members */
        struct person *newly = malloc(sizeof(struct person));
        newly->name = malloc(100);
        newly->ssn = malloc(100);
        printf("enter the %dth person's name t",i+1);
        scanf("%s", newly->name);
        printf("enter %dth person's age t",i+1);
        scanf("%d", &newly->age);
        printf("enter %dth person's ssn t",i+1);
        scanf("%s", newly->ssn);
        insert(newly);
    }
    display();
}

我遗漏的一个额外的位是您可以使用scanf - http://www.crasseux.com/books/ctutorial/String-overflows-with-scanf.html溢出输入缓冲区的部分

您的element节点总是相同的，您永远不会分配一个新的，有效地一次又一次地覆盖相同的事情。

当然这是一个全局变量，所以指针被初始化为NULL，所以它会在第一次写入时崩溃

scanf接受char指针，而不是char**:

scanf("%s", pname);

当你写&pname时，你错误地取了字符指针pname的地址

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