Question

goodsubject-lm：chap6 varunvb $ cat linkedlists.c

#include <stdio.h>

typedef struct island {
  char *name;
  char *opens;
  char *closes;
  struct island *next;
} island;

island amity = {"Amity", "09:00", "17:00", NULL};
island craggy = {"Craggy", "09:00", "18:00", NULL};
island isla_nublar = {"Shutter", "09:00", "19:00", NULL};
island skull = {"Skull", "09:00", "20:00", NULL};
island shutter = {"Shutter", "09:00", ":21:00", NULL};
amity.next = &craggy;
craggy.next = &isla_nublar;
isla_nublar.next = &skull;
skull.next = &shutter;

void display (island *start) {

  island *i = start;

  for (; i != NULL; i == i->next) {
     printf ("Name: %s\nOpens: %s\ncloses: %s\n", i->name, i->opens, i->closes);
     }
}

int main ()
{
 display (&amity);
 display (&craggy);
 display (&isla_nublar);
 display (&skull);
 return 0;
}

我得到的错误如下。

linkedlists.c:15:1: error: unknown type name 'amity'
amity.next = &craggy;
^
linkedlists.c:15:6: error: expected identifier or '('
amity.next = &craggy;
     ^
linkedlists.c:16:1: error: unknown type name 'craggy'
craggy.next = &isla_nublar;
^
linkedlists.c:16:7: error: expected identifier or '('
craggy.next = &isla_nublar;
      ^
linkedlists.c:17:1: error: unknown type name 'isla_nublar'
isla_nublar.next = &skull;
^
linkedlists.c:17:12: error: expected identifier or '('
isla_nublar.next = &skull;
           ^
linkedlists.c:18:1: error: unknown type name 'skull'
skull.next = &shutter;
^
linkedlists.c:18:6: error: expected identifier or '('
skull.next = &shutter;
     ^
linkedlists.c:24:23: warning: equality comparison result unused [-Wunused-comparison]
  for (; i != NULL; i == i->next) {
                    ~~^~~~~~~~~~
linkedlists.c:24:23: note: use '=' to turn this equality comparison into an assignment
  for (; i != NULL; i == i->next) {
                      ^~
                      =
1 warning and 8 errors generated.

Answer 1

clk='1' and clk'event

我认为你的意思是for (; i != NULL; i == i->next) {。你的循环无限或永不运行。

对于您的错误，您不应使用全局变量，而是在代码中创建和链接元素。正如M Oehm评论的那样，至少将你的i = i->next陈述移到主要陈述中。

你可以有一个岛工厂函数，它分配一个指针x.next = &y并填充它，然后返回它。

例如：

island

island *add_island(island *begin, char *name, char *opens, char *closes) { island *new = malloc(sizeof(*new)); if (new == NULL) { printf("Malloc error in add_island"); return NULL; } new->name = name; new->opens = opens; new->closes = closes; new->next = begin; return new; } int main(void) { island *list = add_island(NULL, "last island", "12:00", "02:00"); list = add_island(list, "first island", "20:00", "10:00"); display(list); }可以作为推送列表。

我不知道为什么我的结构没有被设定

1 个答案: