链表实现多项式相加

#include<iostream>
#include<cstdlib>
#include<cmath>
#include<cstdio>
using namespace std;
typedef struct node
{
    float c;
int e;
struct node *next;
}lnode;


void create(lnode *l)
{
lnode *r,*s;
float co;int ex;
scanf("%f%d",&co,&ex);
r=l;
while(co!=0)
{
s=(lnode *)malloc(sizeof(lnode));
s->c=co;s->e=ex;
r->next=s;
r=s;
scanf("%f%d",&co,&ex);
}
r->next=NULL;
}


void print(lnode *l)
{
lnode *p=l->next;
if(p->e==1)
cout<<p->c<<"x";
else
cout<<p->c<<"x^"<<p->e;
while(p->next!=NULL)
{
    p=p->next;
    if(p->e==1)
    cout<<p->c<<"x";
    else
    cout<<"+"<<p->c<<"x^"<<p->e;
}
cout<<endl;
}


lnode *add(lnode *P,lnode *Q)
{
lnode *p,*q,*r,*s;
float sum;
p=P->next;q=Q->next;
r=P;
while(p&&q)
{
if((p->e)<(q->e))
{
r->next=p;
r=r->next;
p=p->next;
}
else if((p->e)>(q->e))
{
r->next=q;
r=r->next;
q=q->next;
}
else
{
sum=(p->c)+(q->c);
if(sum!=0)
{
p->c=sum;
r->next=p;
r=r->next;
p=p->next;
s=q;
q=q->next;
free(s);
}
else
{
s=p;
p=p->next;
free(s);
s=q;
q=q->next;
free(s);
}
}
}
if(p)
r->next=p;
else
r->next=q;
free(Q);
return P;
}


int main()
{
lnode *p,*q;
p=(lnode *)malloc(sizeof(lnode));
q=(lnode *)malloc(sizeof(lnode));
p->next=NULL;
q->next=NULL;
create(p);
print(p);
create(q);
print(q);
print(add(p,q));
return 0;
}