123.cpp

实现一定的功能

#include<stdio.h>
#include<malloc.h>
#define MAX 20  //多项式最多项数
typedef struct  //定义存放多项式的数组类型
{
  float coef;   //系数
  int exp;      //指数
}PolyArray[MAX];
typedef struct pnode  //定义单链表结点类型
{
  float coef;         //系数
  int exp;            //指数
  struct pnode *next;
}PolyNode; 

void DispPoly(PolyNode *L)  //输出多项式
{
 PolyNode *p=L->next;
 if(p->exp!=0)
 printf("%0.1fx^%d",p->coef,p->exp);
 else printf("%0.1f",p->coef);
 while (p->next!=NULL)
 {
  p=p->next;
  if(p->coef>0)
  printf("+%0.1fx^%d",p->coef,p->exp);
  else printf("%0.1fx^%d",p->coef,p->exp);
 }
 printf("\n");
}
void CreateListR(PolyNode * &L,PolyArray a,int n)    //尾插入法建表
{
 PolyNode *s,*r;int i;
 L=(PolyNode *)malloc(sizeof(PolyNode));          //创建头结点
 L->next=NULL;
// L->exp=n;
// printf("%d\n",L->exp);
 r=L;                                            //r始终指向终端结点，开始时指向头结点
  for(i=0;i<n;i++)
  {
    s=(PolyNode *)malloc(sizeof(PolyNode));   //创建新结点
    s->coef=a[i].coef;
    s->exp=a[i].exp;
    r->next=s;                               //将*s插入*r之后
    r=s;
  }
  r->next=NULL;                               //将终端结点next域置为NULL
}
void Sort(PolyNode * &head)                         //按exp域的值递减排序
{
  PolyNode *p=head->next,*q,*r,*t;
  int a;
  float b;
  while(p)                                      //当原单链表不为空时
  {
   r=p;                                     //r保存*p结点后继结点的指针
   q=p->next;                                  //构造只含一个数据结点的有序
   while(q)
   {
	 if(p->exp>q->exp){//r保存*p结点后继结点的指针
     a=p->exp;
     b=p->coef;
     p->coef=q->coef;                               //在有序表中找插入*p的前驱结点*q
     p->exp=q->exp;                             //将*p插入到*q之后
     q->coef=b;
	 q->exp=a;}
	 else if(p->exp==q->exp){
		 p->coef=p->coef+q->coef;
		 t=q;
		 free(t);
	 }
	 r=r->next;
	 q=q->next;
   }
  p=p->next;
  }
}
void Add(PolyNode *ha,PolyNode *hb,PolyNode *&hc)//求两个有序表的并
{
  PolyNode *pa=ha->next,*pb=hb->next,*s,*tc;
  float c;
  hc=(PolyNode *)malloc(sizeof(PolyNode));           //创建头结点
  tc=hc;
  while(pa!=NULL && pb!=NULL)
  {
    if(pa->exp>pb->exp)
 {
   s=(PolyNode *)malloc(sizeof(PolyNode));        //复制结点
   s->exp=pa->exp;s->coef=pa->coef;
   tc->next=s;tc=s;
   pa=pa->next;
 }
 else if(pa->exp<pb->exp)
 {
  s=(PolyNode *)malloc(sizeof(PolyNode));           //复制结点
  s->exp=pb->exp;s->coef=pb->coef;
  tc->next=s;
  tc=s;
  pb=pb->next;
 }
 else                                             //pa->exp=pb->exp时
 {
  c=pa->coef+pb->coef;
 if(c!=0)                                          //系数之和不为0时创建新结点
 {
   s=(PolyNode *)malloc(sizeof(PolyNode));    
   s->exp=pa->exp;
   s->coef=c;
   tc->next=s;
   tc=s;
 }
 pa=pa->next;
 pb=pb->next;
 } 

  }
  if(pb!=NULL)                                     //复制余下结点
   pa=pb;
  while(pa!=NULL)
  {
    s=(PolyNode *)malloc(sizeof(PolyNode));           //复制结点
    s->exp=pa->exp;s->coef=pa->coef;
    tc->next=s;
	tc=s;
    pa=pa->next;
  }
  tc->next=NULL;
} 

void Subs(PolyNode *ha,PolyNode *hb,PolyNode *&hc)   //求两个有序表的差
{
  PolyNode *pa=ha->next,*pb=hb->next,*s,*tc;
  float c;
  hc=(PolyNode *)malloc(sizeof(PolyNode));           //创建头结点
  tc=hc;
  while(pa!=NULL && pb!=NULL)
  {
    if(pa->exp>pb->exp)
 {
   s=(PolyNode *)malloc(sizeof(PolyNode));        //复制结点
   s->exp=pa->exp;
   s->coef=pa->coef;
   tc->next=s;
   tc=s;
   pa=pa->next;
 }
 else if(pa->exp<pb->exp)
 {
  s=(PolyNode *)malloc(sizeof(PolyNode));           //复制结点
  s->exp=pb->exp;
  s->coef=pb->coef;                 //如果前个多项式中的指数小于后个多项式指数加上负号
  tc->next=s;
  tc=s;
  pb=pb->next;
 }
 else                                             //pa->exp=pb->exp时
 {
 c=pa->coef-pb->coef;
 if(c!=0)                                          //系数之差不为0时创建新结点
 {
   s=(PolyNode *)malloc(sizeof(PolyNode));    
   s->exp=pa->exp;s->coef=c;
   tc->next=s;tc=s;
 }
 pa=pa->next;
 pb=pb->next;
 } 

  }
  if(pb!=NULL)                                     //复制余下结点
   pa=pb;
  while(pa!=NULL)
  {
    s=(PolyNode *)malloc(sizeof(PolyNode));           //复制结点
 s->exp=pa->exp;s->coef=pa->coef;
 tc->next=s;tc=s;
 pa=pa->next;
  }
  tc->next=NULL;
}
void main()
{
   PolyNode *ha,*hb,*hc;
   int m,n;
   printf("*********一元多项式的加减法********\n");
   printf("请输入第一个多项式的项数:");
   scanf("%d",&m);
   PolyArray a,b;
   for(int i=0;i<m;i++)
   {
     printf("请输入A多项式中第%d项的系数和指数",i);
     scanf("%f%d",&a[i].coef,&a[i].exp);
   }
   printf("请输入第二个多项式的项数:");
   scanf("%d",&n);
    for(int j=0;j<n;j++)
   {
     printf("请输入B多项式中第%d项的系数和指数",j);
     scanf("%f%d",&b[j].coef,&b[j].exp);
   } 

   CreateListR(ha,a,m);
   CreateListR(hb,b,n);
   printf("原来A:\n");DispPoly(ha);
   printf("原来B:\n");DispPoly(hb); 
   Sort(ha);
   Sort(hb);
   printf("排序后A:\n");
   DispPoly(ha);
   printf("排序后B:\n");
   DispPoly(hb); 
   printf("请输入要执行的运算(1.加法2.减法0.退出)\n");
   case 0:return ;break;
   case 1:
	   Add(ha,hb,hc);
       Sort(hc);
       printf("相加后:\n");
       DispPoly(hc);
	   break;
   case 2:
	   Subs(ha,hb,hc);
       Sort(hc);
       printf("相减后:\n");
       DispPoly(hc);
	   break;
   
}