我这个 一元多项式相加 结果的系数为什么不变呢？（万分感谢）

[gengyigang]

#include "stdlib.h"
typedef struct LNode
{
int coef;
int expn;
struct LNode *next;
}LNode,*ListNode;
ListNode CreateFromTail()
{
ListNode l,p,tail;
int m;
int n;
l=(ListNode)malloc(sizeof(LNode));
l->next=NULL;
tail=l;
printf("\nplease put the coef:");
scanf("%d",&m);
printf("\nplease put the expn:");
scanf("%d",&n);
while(m)
{
p=(ListNode)malloc(sizeof(LNode));
p->coef=m;
p->expn=n;
tail->next=p;
tail=p;
printf("\nplease put the coef:");
scanf("%d",&m);
printf("\nplease put the expn:");
scanf("%d",&n);
}
tail->next=NULL;
return l;
}
ListNode MergeList(ListNode la,ListNode lb)
{
ListNode ra,rb,pa,pb;
int sum;
ra=la;
rb=lb;
pa=la->next;
pb=la->next;
while(pa&&pb)
{
if(pa->expn>pb->expn)
{
ra=ra->next;
pa=pa->next;
}
else if(pa->expn <pb->expn)
{
rb->next=pb->next;
pb->next=ra->next;
ra->next=pb;
ra=ra->next;
pa=ra->next;
pb=rb->next;
}
else
{
if((pa->coef+pb->coef)!=0)
{
sum=pa->coef+pb->coef;
pa->coef=sum;
ra=ra->next;
pa=pa->next;
rb=rb->next;
pb=pb->next;
}
else
{
pa=pa->next;
pb=pb->next;
ra->next=pa;
rb->next=pb;
}
}
}
if(pb)
ra->next=pb;
free(lb);
return la;
}
main()
{
ListNode m,n,l,p;
printf("the first equation:");
m=CreateFromTail();
printf("\n");
printf("the second equation:");
n=CreateFromTail();
l=MergeList(m,n);
p=l->next;
while(p!=NULL)
{
printf(" %d %d\t",p->coef,p->expn);
p=p->next;
}
}

[knowledge_Is_Life]

我也想了解，谢谢LZ.

[meiZiNick]

有点难度哦

[Supercaller]

结果中每一项都有系数,而且经过相加一般都会变化,但是lz说的系数不变有几种可能:
1:你运行时输入的两个多项式中相同指数的两项的系数都为相反数(你的程序自身没错)
2:你运行时输入的两个多项式中根本就不存在任何指数相同的两项(你的程序自身没错)
3:你运行的结果中某些变了,但你没有注意到(你的程序)
4:由于我这里没有工具,所以只能猜测一下,下次希望能找出原因

[C1053710211]

#include "stdlib.h" 
#include <stdio.h> 
typedef struct LNode  
{  
        int coef;  
        int expn;  
        struct LNode *next;  
}LNode,*ListNode;  

ListNode CreateFromTail()  
{  
         ListNode l,p,tail;  
         int m;  
         int n;  
         l=(ListNode)malloc(sizeof(LNode));  
         l->next=NULL;  
         tail=l;  
         printf("\nplease put the coef:");  
         scanf("%d",&m);  
         printf("\nplease put the expn:");  
         scanf("%d",&n);  
         while(m)  
         {  
            p=(ListNode)malloc(sizeof(LNode));  
            p->coef=m;  
            p->expn=n;  
            tail->next=p;  
            tail=p;  
            printf("\nplease put the coef:");  
            scanf("%d",&m);  
            printf("\nplease put the expn:");  
            scanf("%d",&n);  
         }  
         tail->next=NULL;  
         return l;  
}  
ListNode MergeList(ListNode la,ListNode lb)  
{  
         ListNode ra,rb,pa,pb;  
         int sum;  
         ra=la;  
         rb=lb;  
         pa=la->next;  
         pb=lb->next;  //这里你原先是 pb=la->next;
         while(pa&&pb)  
         {  
              if(pa->expn>pb->expn)  
              {  
                ra=ra->next;  
                pa=pa->next;  
              }  
              else if(pa->expn<pb->expn)  
              {  
                 rb->next=pb->next;  
                 pb->next=ra->next;  
                 ra->next=pb;  
                 ra=ra->next;  
                 pa=ra->next;  
                 pb=rb->next;  
              }  
              else  
              {  
                 if((pa->coef+pb->coef)!=0)  
                 {  
                    sum=pa->coef+pb->coef;  
                    pa->coef=sum;  
                    ra=ra->next;  
                    pa=pa->next;  
                    rb=rb->next;  
                    pb=pb->next;  
              }  
              else  
              {  
                 pa=pa->next;  
                 pb=pb->next;  
                 ra->next=pa;  
                 rb->next=pb;  
              }  
         }  
       }  
       if(pb)  
       ra->next=pb;  
       free(lb);  
       return la;  
}  
main()  
{  
   ListNode m,n,l,p;  
   printf("the first equation:");  
   m=CreateFromTail();  
    printf("\n");  
    printf("the second equation:");  
    n=CreateFromTail();  
    l=MergeList(m,n);  
    p=l->next;  
    while(p!=NULL)  
    {  
       printf(" %d %d\t",p->coef,p->expn);  
       p=p->next;  
    }  
    system("pause");
}