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[sedaw]

what`s the warning message bout ?

line 47: error C2037: left of 'value' specifies undefined struct/union 'Node'

TNX ......

the code:

#include <stdio.h>
#include <stdlib.h>
 
typedef struct
{
    int value;
    struct Node* next;
}Node;
 
 
Node* newList(Node *head)
{
    Node *temp;
    int size,i;
    printf("size?");
    scanf("%d",&size);  
    for(i=0; i<size; i++)
    {
        temp=(Node*)malloc(sizeof(Node));
        temp->next=head;
        head=temp;
        printf("value(%d)=?",i+1);
            scanf("%d",&(head->value));
    }
    return(head);
}
 
void printList(Node*head)
{
    Node* current=head;
    while(current!=0)
    {
        printf("%d\n",current->value);
        current=current->next;
    }
}
 
 
sort_list(Node*list)
{
    Node* current=list;
    while(current!=NULL)
    {
        current=list;
        while(current!=NULL)
        {
            if((current->next)->value < current->value)
            {
                //swap
            }
            current=current->next;
        }
        list=list->next;
    }
 
}
 
 
 
int main(void)
{
    Node *head=NULL;
    int sel=-1;
    while(sel!=0)
    {
           printf("1. enter new list\n"
                  "2. print list\n"
                  "3. sort list by value\n"
                  "4. enter node by value\n"
                  "5. reverse list\n"
                  "6. delete node\n"
                  "7. free list\n"
                  "0. quit\n"
                  "==>");
           scanf("%d",&sel);
           switch(sel)
           {
               case 1:
                   head=newList(head);
                   break;
 
               case 2:
                   printList(head);
                   break;
               //case 3:
 
           }
    }
}
 

[weaknessforcats]

Your problem is here:

typedef struct 
{ 
    int value; 
    struct Node* next; 
}Node; 

This says that struct Node is now Node. BUT the typedef is after the compiler has seen the member struct Node* next. Therefore, while the struct is now Node, the member is still struct Node*.

Do this:

struct Node
{ 
    int value; 
    struct Node* next; 
}; 
typedef struct Node Node;

Now struct Node is now Node. So when the compiler sees the struct Node* member it will accept Node* since it knows that struct Node and Node are the same type.

[JosAH]

There is no "struct Node" defined, only an alias for that (unnamed) struct is defined by that typedef; make it:

typedef struct _Node
{ 
    int value; 
    struct _Node* next; 
}Node; 
 

kind regards,

Jos

edit: too late ;-)

[weaknessforcats]

JosAH solution combines my solution of two statements into one statement. The effect is the same. The JosAH solution is the one I usually see in production code.

[sedaw]

ok...., thank you very much !