两个多项式求和问题 有错误求大神修改！

#include<stdio.h>
#include<stdlib.h>
struct node
{
    int exp;
    float coef;
    struct node *next;
    };
typedef struct node ListNode;
ListNode *createpoly()
/*创建多项式列表*/
{
    ListNode *h=NULL,*p,*q=NULL;
    int e;
    float c;
    printf("请输入系数和指数：");
scanf("%f,%d",&c,&e);
while(e!=0||c!=0)
{
    p=(ListNode*)malloc(sizeof(ListNode));
    p->coef=c;
    p->exp=e;
    p->next=NULL;
    if(h==NULL)
         h=p;
    else
        q->next=p;
    q=p;
    printf("请输入系数和指数：");
    scanf("%f,%d",&c,&e);
}
return h;
}
void disppoly(ListNode *h)
/*输出多项式*/
{
    ListNode *p;
    p=h;
    while(p!=NULL)
    {
        if(p->exp==0)
            printf("%.2f",p->coef);
        else
            printf("%fx^%d",p->coef,p->exp);
        p=p->next;
        if(p!=NULL)
           printf("+");
    }
    printf("\n");
}
ListNode *addpoly(ListNode *h1,ListNode *h2)
/*将两个多项式相加*/
{
    ListNode *p,*r=NULL,*s1,*s2,*s=NULL;
    float c;
    int e;
    s1=h1;
    s2=h2;
    while(s1!=NULL&&s2!=NULL)
    {
        if(s1->exp==s2->exp)
        {
            c=s1->coef+s2->coef;
            e=s1->exp;
            s1=s1->next;
            s2=s2->next;
        }
        else if(s1->exp==s2->exp)
        {
            c=s1->coef;
            e=s1->exp;
            s1=s1->next;
        }
        else
        {
            c=s2->coef;
            e=s2->exp;
            s1=s2->next;
        }
        if(c!=0)
        {
            p=(ListNode*)malloc(sizeof(ListNode));
            p->coef=c;
            p->exp=e;
            p->next=NULL;
            if(s==NULL)
                s=p;
            else
                r->next=p;
            r=p;
        }
    }
    while(s1!=NULL)

{
     c=s1->coef;
     e=s1->exp;
     s1=s1->next;
     if(c!=0)
     {
         p=(ListNode*)malloc(sizeof(ListNode));
            p->coef=c;
            p->exp=e;
            p->next=NULL;
            if(s==NULL)
                s=p;
            else
                r->next=p;
            r=p;
     }
    while(s2!=NULL)
  {
     c=s2->coef;
     e=s2->exp;
     s2=s2->next;
     if(c!=0)
     {
         p=(ListNode*)malloc(sizeof(ListNode));
            p->coef=c;
            p->exp=e;
            p->next=NULL;
            if(s==NULL)
                s=p;
            else
                r->next=p;
            r=p;
     }
  }
  
}
return s;
}
void deletepoly(ListNode *h)
/*释放多项式所占用内存单元*/
{
    ListNode *p,*r=h;         
    while(r!=NULL)
    {
        p=r->next;
        free(r);
        r=p;
    }
}
void main()
{
    ListNode *head1,*head2,*head;
    printf("创建第一个多项式：\n");
    head1=createpoly();
    printf("创建第二个多项式:\n");
    head2=createpoly();
    head=addpoly(head1,head2);
    disppoly(head);
    deletepoly(head);
}