c - 尝试打印结构时出现段错误

Question

我正在尝试编写一个代码，允许用户输入他想要的任意数量的条目，然后将它们打印出来(以及其他功能，仍然需要实现)。但是当我尝试启动代码时，它允许我输入条目，但是当我想打印它们时，它不会注册 current.name 或 current.telNo (仅打印出 1: has tel. No. )，并在其后出现段错误。知道我该如何解决这个问题吗？

#include <stdio.h>
#include <stdlib.h>

int listSize;
int counter = 0;

struct Entry {
        char name[20];
        char telNo[9];
        struct Entry *next;
} current;

int main()
{
    struct Entry *linkedList = (struct Entry * )malloc(sizeof(struct Entry));
    struct Entry *current = linkedList;
    first(current);
    print(current);
    return 0;
}

void first(struct Entry linkedList)
{
    int i;
    printf("enter list size: ");
    scanf("%d", &listSize);
    printf("Now enter entries one by one: \n");
    for (i = 0; i < listSize; i++) {
        counter++;
        printf("Name: ");
        scanf("%s", linkedList.name);
        printf("Telephone: ");
        scanf("%s", linkedList.telNo);

        if (i != listSize -1) {
            linkedList.next = (struct Entry *)malloc(sizeof(struct Entry));
            linkedList = *linkedList.next;
        } else {
            linkedList.next = NULL;
        }
    }
}

void print(struct Entry linkedList)
{
    int nr = 1;
    printf("\nTelephone book is:\n");
    while (current.name != NULL) {
        printf("%d: %s has tel. No.\t%s\n", nr, current.name, current.telNo);
        current = *current.next;
        nr++;
    }
}     

Answer 1

而不是 .您应该使用 -> 并且在您的 print() 中您正在遍历 current 而不是 linkedList ，这导致问题。此外，您的函数定义应该在其使用之前。请检查下面的代码片段，我已经做了相应的更改。

#include <stdio.h>
#include <stdlib.h>

int listSize;
int counter = 0;

struct Entry {
    char name[20];
    char telNo[9];
    struct Entry *next;
} current;


void print(struct Entry *linkedList)
{
    int nr = 1;
    printf("\nTelephone book is:\n");
    while (linkedList->name != NULL) {
      printf("%d: %s has tel. No.\t%s\n", nr, linkedList->name, linkedList->telNo);
      linkedList = linkedList->next;
      nr++;
    }

} 
void first(struct Entry *linkedList)
{
    int i;
    printf("enter list size: ");
    scanf("%d", &listSize);
    printf("Now enter entries one by one: \n");
    for (i = 0; i < listSize; i++) {
        counter++;
        printf("Name: ");
        scanf("%s", linkedList->name);
        printf("Telephone: ");
        scanf("%s", linkedList->telNo);

        if (i != listSize -1) {
            linkedList->next = (struct Entry *)malloc(sizeof(struct Entry));
            linkedList = linkedList->next;
        } else {
            linkedList->next = NULL;
        }
    }
}

int main()
{
    struct Entry *linkedList = (struct Entry * )malloc(sizeof(struct Entry));
    struct Entry *current = linkedList;
    first(current);
    print(current);
    return 0;
}