希望通过CreatePolyn 建立一个多项式，实现用户输的节点按指数的大小从小到大排列，若输入的的指数和存在的某个节点的指数相同，则改变那个节点的指数，同时不插入这个节点。运行时，PrintfPolyn 无法正确显示输入的多项式，请高人指点，谢谢了
#include<stdio.h>
#include<malloc.h>
#define TRUE   1
#define FALSE  0
#define OK     1
#define ERROR  0
#define    INFEASIBLE -1
#define OVERFLOW   -2
#define N  3

typedef int Status;
typedef struct Lnode{
    float coef;
    int expn;
    struct Lnode *next;
}Lnode,*polynomial;



Status  CreatePolyn(polynomial &l,int M){
    int i=1;
    polynomial s,p,q;
    l=(polynomial)malloc(sizeof(Lnode));
    if(!l)  return(OVERFLOW);
    l->next=NULL;
    //插入第一个节点
    q=(polynomial)malloc(sizeof(Lnode));
    if(!q)  return(OVERFLOW);
    printf("请用户输入多项式中第%d项的系数及指数，中间用空格隔开:\n",i);
    scanf("%f %d",&(q->coef),&(q->expn));
    q->next=l->next;
    l->next=q;
    //其他节点在选择插入位置时考虑指数大小        
    for(i=2;i<=M;i++)
    {
        p=l->next;//p每次指向第一个结点
        q=(polynomial)malloc(sizeof(Lnode));
        if(!q)  return(OVERFLOW);
        printf("请用户输入多项式中第%d项的系数及指数，中间用空格隔开:\n",i);
        scanf("%f %d",&(q->coef),&(q->expn));
        if(q->expn<p->expn){//在p点前插
            q->next=p;
            l->next=q;
        }
        else{
            while((p->expn<q->expn)&&(p->next!=NULL))
            {
                s=p;
                p=p->next;
            }
            if(q->expn==p->expn)
            {
                p->coef+=q->coef;
                free(q);
            }
            else if(p->expn>q->expn)
            {
                q->next=s->next;
                s->next=q;
            }
            else
            {
                q->next=p->next;
                p->next=q;
            }
        }
    }
    return OK;
}

Status PrintPolyn(polynomial &l){
    polynomial p;
    p=l->next;
    printf("该多项式是:\n");
    while(p){
        printf("%f*X[%d]  ",p->coef,p->expn);
    }
    return OK;
}

        
void main()
{
    polynomial l;
    if(CreatePolyn(l,N))
        printf("createpolyn...");
    PrintPolyn(la);
    

}

没人顶，自己回一下

大家帮帮忙啊