用单链表及c语言创建多项式

Question

为什么这个代码无法运行？个人感觉应该没有死循环啊

#include <stdio.h>
#include <stdlib.h>
typedef struct pNode{
    int coef;           //x系数域
    int exp;            //指数域
    struct pNode* link;         指针域
}PNode;
typedef struct polynominal{
    PNode *head;
}Polynominal;
void Creat(Polynominal *h);
//void Output(Polynominal *h);
void Destroy(Polynominal *h);
int main()
{
    Polynominal *p;
    p=(Polynominal*)malloc(sizeof(Polynominal));
    if (!p) 
        exit(1);
    Creat(p);
   // Output(p);
    Destroy(p);
    return 0;
}
void Creat(Polynominal *h)
{
    int i,x,m;PNode *p,*q;
    h->head=(PNode*)malloc(sizeof(PNode));
    if (!h->head) 
        exit(1);
    h->head->exp=-1;
    h->head->link=h->head;
    printf("input the number of the node:");
    scanf("%d",&x);
    for(i=0;i<x;i++)
    {
        p=(PNode*)malloc(sizeof(PNode));
        printf("input the coef and the exp:");
        do{
            scanf("%d%d",&p->coef,&p->exp);
        }while(p->exp<0);
        q=h->head;
        for(m=0;m<=i;m++)
        {
            if (q == q->link)   //当仅有头结点时
            {
                p->link = q;
                q->link = p;
            } 
            else 
            {
                if (p->exp > ((q->link)->exp)&&q->link!=h->head)    //当p>q->link且q不为最后一个节点时
                {
                    q = q->link;
                } 
                else 
                {
                    p->link = q->link;
                    q->link = p;
                    break;
                }
            }
        }
    }
}

void Destroy(Polynominal *h)
{
    PNode *p;
    while(h->head)
    {
        p=h->head->link;
        free(h->head);
        h->head=p;
    }
}

Answer 1

找到错了，第七行指针域没注释