初学者求改错啊，我用的是vc6显示没错误，但是出不了结果怎么回事啊？帮忙看看，谢谢啊！！！！！

#include <stdio.h>//递增有序单链表，删除表中相同的多余元素
#include <stdlib.h>
typedef char DataType;
typedef struct Node
{
    DataType data;
    struct Node *next;
}LinkList;
void DeleteSame(LinkList *L);
int main(void)
{
    LinkList *head = NULL;
    LinkList *L = NULL;
    LinkList *p = NULL, *q = NULL;
    char ch;
    head = malloc (sizeof (LinkList));
    head->next = NULL;
    while ((ch=getchar()) != '$')
    {
        L = malloc (sizeof(LinkList));
        L->data = ch;
        p = head;
        q = head->next;
        while (NULL!=q && q->data<=ch)
        {
            p = p->next;
            q = q->next;
        }
        L->next = p->next;
        p->next = L;
        //flushall();
    }
    //输出未经处理的字样
    p = head->next;
    while (NULL != p)
    {
        printf("%c", p->data);
        p = p->next;
    }
    printf("\n");
    DeleteSame(head);
    //输出经过处理的字样
    p = head->next;
    while (NULL != p)
    {
        printf("%c", p->data);
        p = p->next;
    }
    printf("\n");
    return 0;
}
void DeleteSame(LinkList *L)
{
    LinkList *p=NULL, *fp=NULL, *t=NULL;
    fp = L->next;
    p = fp->next;
    while (NULL !=fp && NULL != p)
    {
        if (p->data == fp->data)
        {
            t = p;
            fp->next = p->next;
            p = p->next;
            free(t);
        }
        else
        {
            fp = fp->next;
            p = p->next;
        }
    }
}