一元稀疏多项式计算器.cpp

一元多项式的计算,建立两个多项式

//=====================Program Description======================
//Title:一元多项式计算
//Function:建立两个多项式，并进行相加，相减运算，输出结果
//@author:王伟
//@版权没有，盗版不究
//参考资料：严蔚敏《数据结构与算法》
//==============================================================
#include<stdio.h> //声明部分：源代码含有2个文件
#include<malloc.h>
typedef struct pnode // 定义指针//

{
	int coef; //定义系数//
	int exp; //定义指数//
	struct pnode *next;
}
pnode;
pnode * creat() //creat函数用来存放多项式//
{
	int m,n;
	pnode *head,*rear,*s;
	head=(pnode *)malloc(sizeof(pnode));
	rear=head;
	printf("\n输入指数(按递增顺序输入)：");
	scanf("%d",&m);
	printf("输入一元式系数(0为退出)：");
	scanf("%d",&n);
	do
	{
		s=(pnode *)malloc(sizeof(pnode));
		s->coef=n; //n为系数//
		s->exp=m; //m为指数//
		rear->next=s;
		s->next=NULL;
		rear=s;
		printf("\n输入指数(按递增顺序输入)：");
		scanf("%d",&m);
		printf("输入一元式系数(0为退出)：");
		scanf("%d",&n);
	}
	while(n);
	return head;
}

pnode * add(pnode *heada,pnode *headb)
{
	pnode *headc,*a,*b,*s,*rearc;
	int sum;
	a=heada->next;b=headb->next;
	headc=(pnode *)malloc(sizeof(pnode));
	rearc=headc;
	//多项式的存放//都放到s中里//
	while(a!=NULL&&b!=NULL) //指数相等，则系数相加。
	{
		if(a->exp==b->exp)
		{ 
			sum=a->coef+b->coef;
			if(sum)
			{
				s=(pnode *)malloc(sizeof(pnode));
				s->coef=sum;
				s->exp=a->exp;
				rearc->next=s;
				rearc=s;
				a=a->next;
				b=b->next;}
			else
			{
				a=a->next;
				b=b->next;
			}
		}
		else if(a->exp<b->exp) //a指数如果小于b，则a放到s中//
		{ 
			s=(pnode *)malloc(sizeof(pnode));
			s->coef=a->coef;
			s->exp=a->exp;
			rearc->next=s; 
			//用下一个结点s取代下一个c//
			rearc=s;
			a=a->next;
		}
		else //如果a的指数大，则b放到s中//
		{ 
			s=(pnode *)malloc(sizeof(pnode));
			s->coef=b->coef;
			s->exp=b->exp;
			rearc->next=s;
			rearc=s;
			b=b->next;
		}
	}
	if(a)
	{
		while(a!=NULL) //b空了放a中的项//
		{
			s=(pnode *)malloc(sizeof(pnode));
			s->coef=a->coef;
			s->exp=a->exp;
			rearc->next=s;
			s->next=NULL;
			rearc=s;
			a=a->next;
		}
	}
	else if(b)
	{
		while(b!=NULL) //a空了放b中的项//
		{
			s=(pnode *)malloc(sizeof(pnode));
			s->coef=b->coef;
			s->exp=b->exp;
			rearc->next=s;
			s->next=NULL;
			rearc=s;
			b=b->next;
		}
	}
	return headc;
}
void main()
{
	pnode *a,*b,*c;
	printf("建立A:");
	a=creat();
	printf("\n建立B:");
	b=creat();
	c=add(a,b);
	c=c->next;
	printf("%dx^%d",c->coef,c->exp);
	c=c->next;
	while(c!=NULL)
	{
		printf("+%dx^%d",c->coef,c->exp);
		c=c->next;
	}
}