#include<stdio.h>
#include<malloc.h>
   
typedef struct PolyNode *Poly;
struct PolyNode{
       int coef;
       int expon;
       struct PolyNode *next;
  };
  
  void attach(int c,int e,Poly *p);
  Poly ReadPoly();
  Poly Add(Poly p1,Poly p2);
  void PrintPoly(Poly p);
 
  int main()
  {
      Poly p1,p2,pa;
      p1=ReadPoly();
      p2=ReadPoly();
     
     
   
      pa=Add(p1,p2);
   
      PrintPoly(pa);
     
      return 0;
  }
  
   
  Poly ReadPoly()
   {
       int N,c,e;
      Poly p,rear,t;
     scanf("%d",&N);
      
      p=(Poly)malloc(sizeof(struct PolyNode));
      p->next=NULL;
      rear=p;
     
      while(N--){
          scanf("%d %d",&c,&e);
         attach(c,e,&rear);
      }
      
      t=p;
      p=p->next;
      free(t);
  
      return p;
   }
  
  
   void attach(int c,int e,Poly *p)
   {
       Poly addnode;
       addnode=(Poly)malloc(sizeof(struct PolyNode));
      addnode->coef=c;
       addnode->expon=e;
      addnode->next=NULL;
       (*p)->next=addnode;
       *p=addnode;
   }
   
  
   
   Poly Add(Poly p1,Poly p2)
   {
       Poly p,t1,t2,rear,temp;
       t1=p1;
      t2=p2;
       p=(Poly)malloc(sizeof(struct PolyNode));
       p->next=NULL;
       rear=p;
      
      while(t1&&t2){
          if(t1->expon==t2->expon){
              if((t1->coef+t2->coef)!=0){
               attach(t1->coef+t2->coef,t1->expon,&rear);
              }
             t1=t1->next;
             t2=t2->next;
          }
         else if(t1->expon>t2->expon){
              attach(t1->coef,t1->expon,&rear);
              t1=t1->next;
          }
         else {
          attach(t2->coef,t2->expon,&rear);
          t2=t2->next;
         }
      }
      for(;t1;t1=t1->next)attach(t1->coef,t1->expon,&rear);
     for(;t2;t2=t2->next)attach(t2->coef,t2->expon,&rear);
      rear->next=NULL;
      temp=p;
      p=p->next;
      free(temp);
      return p;
  }
  void PrintPoly(Poly p)
  {
      int flag=0;
     
      if(!p){
         printf("0 0");
      }
     
     while(p){
          if(!flag)flag=1;
          else printf(" ");
         
          printf("%d %d",p->coef,p->expon);
         p=p->next;
      }
     printf("\n");
   }

没有觉得哪有错啊，运行结果也没有问题啊

这应该是一元多项式的求和吧。
代码两个不足之处, 一个是链表没有排序。如果是乱序输入，可能结果就不是你想要的。
                 一个是最后没有释放结点。既然用了malloc，那么用完之后free也是必不可少的。

反正 这 源码  看的 我也是 懵逼了 。没任何 注释。（谁有 那么多时间 慢慢了解你的  意图）