add_multiply_polyn.cpp

两个一元多项式相加相乘源程序。用C++编写。

//Add_Multiply_Polyn.cpp
//Add Polynomial Pa and Pb or Multiply Pa and Pb

#include <conio.h>
#include <iostream.h>
#include <malloc.h>

struct term
{   //Typedef LinkList with Polynomial
	float coef;
	int expn;
	struct term *next;
}*Polynomial;

void CreatPolyn(struct term * &Polyn,int m)
{   //To Creatre a polynomial Polyn with HeadNode
	int i;
    struct term *q;
	Polyn=(struct term *)malloc(sizeof(term));
	Polyn->next=NULL;
	for(i=m;i>0;--i)
	{   //Reverse order inputing for Creating a Polynomial
		q=(struct term *)malloc(sizeof(term));
		cout<<"coef=";
        cin>>q->coef;
        cout<<"expn=";
        cin>>q->expn;
        q->next=Polyn->next;
        Polyn->next=q;
	}//end of for
    if(m) cout<<"Success to Create a Polynomial!"<<endl;
		else cout<<"A NULL LinkList have been created!"<<endl;
} //end of CreatPolyn() function

void IsDescending(struct term * &Polyn)
{   //To descend the polynomial Polyn
    int temp0,temp1;
    struct term *q0,*q1;
	q0=Polyn->next;
    do
    {
		q1=Polyn->next;
        do
        {
			if(q0->expn>q1->expn)
            {
				temp0=q0->coef;q0->coef=q1->coef;q1->coef=temp0;
				temp1=q0->expn;q0->expn=q1->expn;q1->expn=temp1;
            }
            q1=q1->next;
		}while(q1!=NULL);//end of the second do---while
        q0=q0->next;
	}while(q0!=NULL);//end of the first do---while
}//end of IsDescending() function

void MergePolyn(struct term * &Polyn,struct term * &L)
{   //To merge like terms
	struct term *q0,*temp;
    L=(struct term *)malloc(sizeof(term));
    L->next=NULL;
    q0=Polyn->next;
    temp=(struct term *)malloc(sizeof(term));
    temp->coef=q0->coef;temp->expn=q0->expn;
    temp->next=L->next;L->next=temp;
    q0=q0->next;
    while(q0)
    {
        if(q0->expn==temp->expn)
		{
			temp->coef+=q0->coef;
        }
        else
        {
            temp=(struct term *)malloc(sizeof(term));
            temp->coef=q0->coef;temp->expn=q0->expn;
            temp->next=L->next;L->next=temp;
		}//end of if---else
        q0=q0->next;
	} //end of while
} //end of MergePolyn() function

void AddPolyn(struct term * &Pa,struct term * &Pb,struct term * &Pc)
{   //To add Polynomial Pa and Pb
    struct term *qa,*qb,*qc;
    Pc=(struct term *)malloc(sizeof(term));
    Pc->next=NULL;
    qa=Pa->next;
    qb=Pb->next;
	while(qa&&qb)
        {
			qc=(struct term *)malloc(sizeof(term));
            if(qa->expn>qb->expn)
            {
				qc->coef=qa->coef;qc->expn=qa->expn;
				qa=qa->next;
            }
				else if(qa->expn==qb->expn)
				{
                    qc->coef=qa->coef+qb->coef;qc->expn=qa->expn;
					qa=qa->next;qb=qb->next;
                }
					else
                        {
							 qc->coef=qb->coef;qc->expn=qb->expn;
							 qb=qb->next;
						}//end of if---else
			qc->next=Pc->next;Pc->next=qc;
		}//end of while
    if(qa&&!qb)
    {
         while(qa)
         {
             qc=(struct term *)malloc(sizeof(term));
             qc->coef=qa->coef;qc->expn=qa->expn;qa=qa->next;
             qc->next=Pc->next;Pc->next=qc;
		 }//end of while
	}//end of if
    if(!qa&&qb)
    {
        while(qb)
         {
             qc=(struct term *)malloc(sizeof(term));
             qc->coef=qb->coef;qc->expn=qb->expn;qb=qb->next;
             qc->next=Pc->next;Pc->next=qc;
		 }//end of while
	}//end of else
}//end of AddPolyn() function

void MultiplyPolyn(struct term * &Pa,struct term * &Pb,struct term * &Pd)
{   //To multiply Polynomial Pa and Pb
    struct term *qa,*qb,*qd;
    Pd=(struct term *)malloc(sizeof(term));
    Pd->next=NULL;
    qa=Pa->next;
    qb=Pb->next;
    for(qa=Pa->next;qa!=NULL;)
    {
        qb=Pb->next;
        for(;qb!=NULL;qb=qb->next)
        {
            qd=(struct term *)malloc(sizeof(term));
            qd->coef=(qa->coef)*(qb->coef);
            qd->expn=(qa->expn)+(qb->expn);
			qd->next=Pd->next;Pd->next=qd;
		}//end of the second for
        qb=Pb->next;qa=qa->next;
	}//end of the first for

}//end of MultiplyPolyn() function

void DisplayPolyn(struct term * &Polyn)
{   //To display the result
	struct term *temp;
	temp=Polyn;
	while(temp->next)
	{
		temp=temp->next;
        cout<<"(Pc.coef="<<temp->coef<<",";
		cout<<"Pc.expn="<<temp->expn<<")"<<endl;
	}//end of while
	cout<<endl<<"OK...!"<<endl;
} //end of DisplayPolyn() function

void main()
{   //The main() function
	char x;
	struct term *Pa,*Pb,*Pc,*Pd,*La,*Lb,*Lc,*Ld,*add,*multiply;
    int PolynLength_Pa,PolynLength_Pb;
	cout<<"Add_Multiply_Polyn.cpp"<<endl<<"========================="<<endl;
	cout<<endl<<"How many sessions of polynomial Pa do you want? (eg. 4): ";
	cin>>PolynLength_Pa;
    cout<<"Please input the Pa.coef and Pa.expn in descent order:"<<endl;
    cout<<"For example: (coef=3,expn=21);(coef=7,expn=9);(coef=4,expn=1);(coef=5,expn=0)"<<endl;
	CreatPolyn(Pa,PolynLength_Pa);
	IsDescending(Pa);
	MergePolyn(Pa,La);
    cout<<endl<<"How many sessions of polynomial Pb do you want ? (eg. 3): ";
    cin>>PolynLength_Pb;
    cout<<"Please input the Pb.coef and Pb.expn in descent order:"<<endl;
    cout<<"For example: (coef=-7,expn=9);(coef=13,expn=6);(coef=8,expn=1)"<<endl;
    CreatPolyn(Pb,PolynLength_Pb);
    IsDescending(Pb);
    MergePolyn(Pb,Lb);
    cout<<"Which operation do you want to run,add or multiply? (eg. + or *): ";
    cin>>x;
	if(x=='+')
    {
		AddPolyn(Pa,Pb,Pc);
        IsDescending(Pc);
        MergePolyn(Pc,Lc);
		cout<<"Result:"<<endl;
		DisplayPolyn(Lc);
    }
    if(x=='*')
    {
        MultiplyPolyn(Pa,Pb,Pd);
        IsDescending(Pd);
        MergePolyn(Pd,Ld);
        cout<<"Result:"<<endl;
        DisplayPolyn(Ld);
    }
	getch();
}//end of main() function