以这种方式解决它的编译时的链表创建问题[关闭]

Question

帮忙看看上面写着 //PLEASE TELL ME PROBLEM IN THIS LINE

包括

#include <stdlib.h>   

// A linked list node 
typedef struct Node 
{ 
int info; 
struct Node *link; 
}node; 

//insert in a linked list

void insert(node* head, int k)
{
 node* temp = (node*) malloc(sizeof(node));
if(temp==NULL)
  {
      printf("malloc was unsuccessfull");
      exit(0);
  }
  else
  {
      temp->info=k;
      temp->link=NULL;
      if(head==NULL)
      head = temp;
      else
      {
      temp->link=head;
      head=temp;
      }
  }

  // This function prints contents of linked list starting from head 
void print(node* a) 
{ 
  while (a != NULL) 
  { 
     printf(" %d ", a->link); //PLEASE TELL ME PROBLEM IN THIS LINE
     a = a->link; 
  } 
}

}
void main() 
{ 
  /* Start with the empty list */
  node* head = NULL;

  insert(head, 7);
  insert(head, 9);

  printf("\n Created Linked list is: "); 
  print(head); //PLEASE TELL ME PROBLEM IN THIS LINE

}  

错误消息

prog.c: In function 'print':

prog.c:40:13: warning: format '%d' expects argument of type 'int', but argument 2 has type 'struct Node *' [-Wformat=]
      printf(" %d ", a->link); 
             ^
prog.c: In function 'main':

prog.c:55:3: warning: implicit declaration of function 'print' [-Wimplicit-function-declaration]
   print(head);
   ^


/tmp/cc1HDBBm.o: In function `main':
3192773816853040ef42d0aa4269a062.c:(.text+0xeb): undefined reference to `print'
collect2: error: ld returned 1 exit status

Answer 1

1. printf(" %d ", a->link); 行的类型为%d，参数为node。你在这里想要的是打印整数

   printf(" %d ", a->info);
   

2. insert 函数的括号未对齐。在原始代码中，print 的定义在insert 的定义中。您需要正确关闭 insert 函数的括号，并且对 print(head); 的调用将收到正确的定义。并正常工作。

3. 你使用的是void main()，不带任何命令行参数的main的正确格式是int main(void)

Answer 2

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

struct Node {

    int information;
    struct Node* next;
};

struct Node* Create_Node (void);
void Insert_Node (struct Node* target, int information);
void Print_Node (struct Node* head);

int main (int argc, char* argv[]) {

    struct Node* head = NULL;
    head = Create_Node();
    head->next = NULL;

    Insert_Node (head, 7);
    Insert_Node (head, 9);

    printf ("\nCreate Linked list is : ");
    Print_Node (head);

    // free head
    if (head != NULL) head = NULL;
    free (head);

    return 0;
}

void Print_Node (struct Node* head) {

    struct Node* current = NULL;
    current = head->next;

    while (current != NULL) {

        printf ("%3d ", current->information);
        current = current->next;
    }
    printf ("\n");


    // free current
    while (current != NULL) {

        struct Node* next = current->next;
        if (current != NULL) current = NULL;
        free (current);
        current = next;
    }

    return;
}

void Insert_Node (struct Node* target, int _information) {

    struct Node* New_Node = NULL;
    New_Node = Create_Node();
    New_Node->next = target->next;

    // data
    New_Node->information = _information;

    target->next = New_Node;

    return;
}

struct Node* Create_Node (void) {

    struct Node* Pointer_Return = NULL;
    Pointer_Return = (struct Node*) calloc (1, sizeof (struct Node));

    if (Pointer_Return == NULL) {

        printf ("Error! Dynamic memory allocation, Create_Node()\n");
        return NULL;
    }
    return Pointer_Return;
}