利用单链表实现一元多项式的表示及相加

#include <iostream>using namespace std;//定义结构体；typedef struct Polynode{    int coef;    int exp;    struct Polynode *next;}Polynode,*Polylist;//创建关于多项式结构体的单链表，以系数0结束输入Polylist Polycreate(){    Polynode *head,*rear,*s;    int c,e;    head=(Polynode *)malloc(sizeof(Polynode));//申请空间建立多项式的头结点    rear=head;    scanf("%d %d",&c,&e);    while(c!=0)    {        s=(Polynode *)malloc(sizeof(Polynode));        s->coef=c;        s->exp=e;        rear->next=s;        rear=s;        scanf("%d %d",&c,&e);    }//尾插法建立单链表    rear->next=NULL;    return(head);}//多项式polya和polyb相加，结果存放在head单链表中Polylist Polyadd(Polylist polya,Polylist polyb){    Polynode *head,*p,*q,*tail,*s;//head为相加后单链表的头结点，tail为尾插法的尾巴节点    int sum;    head=(Polynode *)malloc(sizeof(Polynode));    p=polya->next;    q=polyb->next;    tail=head;    while(p!=NULL&&q!=NULL)    {        s=(Polynode *)malloc(sizeof(Polynode));        if(p->exp<q->exp)        {            s->coef=p->coef;            s->exp=p->exp;            tail->next=s;            tail=s;            p=p->next;        }        else if(p->exp==q->exp)        {            sum=p->coef+q->coef;            if(sum!=0)            {                s->coef=sum;                s->exp=p->exp;                tail->next=s;                tail=s;                p=p->next;                q=q->next;            }            else return(head);        }        else        {            s->coef=q->coef;            s->exp=q->exp;            tail->next=s;            tail=s;            q=q->next;        }    }    if(p!=NULL)        tail->next=p;    else        tail->next=q;    return(head);}//打印多项式void show(Polylist poly){    Polynode *p;    int c;    int e;    p=poly->next;    while(p->next!=NULL)//避免最后一项也出现加号    {        c=p->coef;        e=p->exp;        PRintf("%dX^%d+",c,e);        p=p->next;    }    c=p->coef;    e=p->exp;    printf("%dX^%d",c,e);}int main(){    printf("请按升幂输入多项式A,以系数为0结束：/n");    Polylist pa=Polycreate();    printf("你输入的多项式为：/n");    show(pa);    printf("/n");    printf("请按升幂输入多项式B,以系数为0结束：/n");    Polylist pb=Polycreate();    printf("你输入的多项式为：/n");    show(pb);    printf("/n");    Polylist pc=Polyadd(pa,pb);    printf("相加之后的多项式为：/n");    show(pc);    return 0;}
实验结果如下：