请教各位大虾我的C程序哪里有错!急!!!

#include"stdio.h"
#include"math.h"
 typedef struct linknode
         {
            int data;
            struct linknode *next;
         }node;
        
node *create(A)
     node *A;
     {
        node *r,*s,*p;
        A=s=(node *)malloc(sizeof(node));
        scanf("%d",&s->data);
        r=s;
        while(s->data!=0)
        {
            r->next=s;
            r=s;
            s=(node *)malloc(sizeof(node));
            scanf("%d",&s->data);
        }
        p=A;
        A=A->next;
        r->next=NULL;
        free p;
        do{
            printf("%d->",A->data);
            A=A->next;
        }while(A!=0);
        return A;
     }
    
node *create(B)
     node *B;
     {
        node *r,*s,*p;
        B=s=(node *)malloc(sizeof(node));
        scanf("%d",&s->data);
        r=s;
        while(s->data!=0)
        {
            r->next=s;
            r=s;
            s=(node *)malloc(sizeof(node));
            scanf("%d",&s->data);
        }
        p=B;
        B=B->next;
        r->next=NULL;
        free p;
        do{
            printf("%d->",B->data);
            B=B->next;
        }while(B!=0);
        return B;
     }
    
node *sum(a,b)
    node *a,*b;
    {
        node *r,*p,*s;
        c=(node *)malloc(sizeof(node));
        r=c;
        while(a!=0)
        {
            r->data=a->data;
            a=a->next;
            p=(node *)malloc(sizeof(node));
            r->next=p;
            r=p;
        }
        while(b!=0)
        {
            p=(node *)malloc(sizeof(node));
            r->next=p;
            r=p;
            r->data=b->data;
            b=b->next;
        }
        r->next=NULL;
        free r;
        free p;
        return c;
    }
   
main()
{
    node *k,*i,*j,*A,*B;
   i=node *create(A);
   j=node *create(B);
    k=node *sum(i,j);
    do{
        printf"%d->",k->data);
        k=k->next;
    }while(k!=0);
} 

目的是先建立两个链表,然后把它们合并在一起,相同的不删除