C语言单链表实现多项式相加

//多项式的相加和相乘 
#include<stdio.h>
#include<stdlib.h>
#pragma warning(disable:4996)//兼容scanf
typedef struct node {
  int coef;
  int expon;
  struct node* link;
}polynode,*polynomial;
polynomial InsertpolylinkList(polynomial in,polynomial Pread) {
  Pread->link = in;
  Pread = in;
  in->link = NulL;
  return Pread;
}
polynomial Readpoly(voID) {

  polynomial Pread = (polynomial)malloc(sizeof(polynodE));
  Pread->link = NulL;
  polynomial H = Pread;
  int n;
  scanf("%d ",&N);
  while (N--) {
    polynomial p = (polynomial)malloc(sizeof(polynodE));
    scanf("%d %d",&p->coef,&p->expon);
    Pread= InsertpolylinkList(p,Pread);
  }
  polynomial F;
  F = H->link;
  free(H);
  return F;
}
voID Printpoly(polynomial F) {
  while(F != NulL) {
    printf("%d %d ",F->coef,F->expon);
    F = F->link;
  }
  printf("\n");
}
polynomial Add(polynomial p1,polynomial p2) {
  polynomial t1=p1,t2=p2;
  polynomial p=(polynomial)malloc(sizeof(polynodE));
  p->link = NulL;
  polynomial q = p;
  polynomial read;
  while (t1&&t2) {
    if (t1->expon == t2->expon) {
      if (t1->coef + t2->coef) {
        t1->coef = t1->coef + t2->coef;
        t1->expon = t1->expon;
        read = t1;
        q->link = read;
        q = read;
        t1 = t1->link;
        t2 = t2->link;   
      }
    }
    else {
      if (t1->expon > t2->expon){
        read = t1;
        q->link = read;
        q = read;
        t1 = t1->link;
      }
      else {
        if (t1->expon < t2->expon) {
          read = t2;
          q->link = read;
          q = read;
          t2 = t2->link;
        }
      }
    }
  }    
  if (t1) {
    q->link = t1;
  }
  if (t2) {
    q->link = t2;
  }
  polynomial F = p->link;
  free(p);
    return F;
}
int main(voID) {
  polynomial p1,p2,pp,ps;
  p1 = Readpoly();
  Printpoly(p1);
  p2 = Readpoly();
  Printpoly(p2);
  pp = Add(p1,p2);
  Printpoly(pp);
// ps = Mult(p1,p2);
// Printpoly(ps);
  return 0;
}