链表逆序问题

#include <stdio.h>

typedef struct node_ {
    int data;
    struct node_* next;
} node;

void list_print( const node* head )
{
    for( ; head; head=head->next )
        printf( "%d%c", head->data, " \n"[head->next==NULL] );
}

node* list_reverse( node* head )
{
    node* pre = NULL;
    for( ; head; )
    {
        node* tmp = head->next;
        head->next = pre;
        pre = head;
        head = tmp;
    }
    return pre;
}

int main( void )
{
    node a[3] = { {0,a+1}, {1,a+2}, {2,NULL} };
   

    node* head = &a[0];
    list_print( head );
   

    head = list_reverse( head );
    list_print( head );
}