线性表，创建多项式的问题

Question

这是一个关于线性表，创建多项式的问题
感觉理论上下面两张图画圈的部分输出的东西应该是一样的
但是不知道为什么输出的时候主函数里的那个printf输出的很奇怪

以一项多项式 x 为例 输出结果如图

代码如下：

#include <stdio.h>
#include <stdlib.h>

typedef struct PNode
{
    float coef;             //系数
    int expn;               //指数
    struct PNode *next;    //指针域
}PNode,*Polynomial;

void CreatePolyn(Polynomial p,int n)
{
    p=(Polynomial)malloc(sizeof(PNode));
    p->next=NULL;
    for(int i=1;i<=n;i++)
    {
        Polynomial s,pre,q;
        s=(Polynomial)malloc(sizeof(PNode));
        scanf("%f%d",&s->coef,&s->expn);
        pre=p;
        q=p->next;
        while(q && q->expn <s->expn)
        {
            pre=q;
            q=q->next;
        }
        s->next=q;
        pre->next=s;
        printf("%f   %d\n",p->next->coef,p->next->expn);
    }

}


int main()
{
    int m,n;
    PNode x,y;
    Polynomial p=&x,q=&y;
    scanf("%d",&m);
    CreatePolyn(p,m);
    while(p->next)
        printf("%f   %d\n",p->next->coef,p->next->expn);
    return 0;
}

Answer 1

#include <stdio.h>
#include <stdlib.h>

typedef struct PNode
{
    float coef;         //系数
    int expn;           //指数
    struct PNode *next; //指针域
} PNode, *Polynomial;

void CreatePolyn(Polynomial p, int n)
{
    // p = (Polynomial)malloc(sizeof(PNode)); // 删除此行，因为main函数已经传入头节点指针
    p->next = NULL;
    for (int i = 1; i <= n; i++)
    {
        Polynomial s, pre, q;
        s = (Polynomial)malloc(sizeof(PNode));
        scanf("%f%d", &s->coef, &s->expn);
        pre = p;
        q = p->next;
        while (q && q->expn < s->expn)
        {
            pre = q;
            q = q->next;
        }
        s->next = q;
        pre->next = s;
        printf("%f   %d\n", p->next->coef, p->next->expn);
    }
}

int main()
{
    int m, n;
    PNode x, y;
    Polynomial p = &x, q = &y;
    scanf("%d", &m);
    CreatePolyn(p, m);
    while (p->next)
    {
        printf("%f   %d\n", p->next->coef, p->next->expn);
        p = p->next;
    }
    return 0;
}