第四周项目6 多项式求和

#include <stdio.h>  
#include <malloc.h>  
#define MAX 20           
typedef struct       
{  
    double coef;          
    int exp;             
} PolyArray;  
  
typedef struct pnode   
{  
    double coef;         
    int exp;              
    struct pnode *next;  
} PolyNode;  
  
void DispPoly(PolyNode *L)    
{  
    bool first=true;          
    PolyNode *p=L->next;  
    while (p!=NULL)  
    {  
        if (first)  
            first=false;  
        else if (p->coef>0)  
            printf("+");  
        if (p->exp==0)  
            printf("%g",p->coef);  
        else if (p->exp==1)  
            printf("%gx",p->coef);  
        else  
            printf("%gx^%d",p->coef,p->exp);  
        p=p->next;  
    }  
    printf("\n");  
}  
  
void DestroyList(PolyNode *&L)   
{  
    PolyNode *p=L,*q=p->next;  
    while (q!=NULL)  
    {  
        free(p);  
        p=q;  
        q=p->next;  
    }  
    free(p);  
}  
  
void CreateListR(PolyNode *&L, PolyArray a[], int n)   
{  
    PolyNode *s,*r;  
    int i;  
    L=(PolyNode *)malloc(sizeof(PolyNode)); //创建头结点  
    L->next=NULL;  
    r=L;                        
    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;                
        r=s;  
    }  
    r->next=NULL;               
}  
  
void Sort(PolyNode *&head)      
{  
    PolyNode *p=head->next,*q,*r;  
    if (p!=NULL)                 
    {  
        r=p->next;               
        p->next=NULL;          
        p=r;  
        while (p!=NULL)  
        {  
            r=p->next;           
            q=head;  
            while (q->next!=NULL && q->next->exp>p->exp)  
                q=q->next;        
            p->next=q->next;      
            q->next=p;  
            p=r;  
        }  
    }  
}  
  
void Add(PolyNode *ha,PolyNode *hb,PolyNode *&hc)    
{  
    PolyNode *pa=ha->next,*pb=hb->next,*s,*tc;  
    double c;  
    hc=(PolyNode *)malloc(sizeof(PolyNode));          
    tc=hc;  
    while (pa!=NULL && pb!=NULL)  
    {  
        if (pa->exp>pb->exp)  
        {  
            s=(PolyNode *)malloc(sizeof(PolyNode));   
            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));
            s->exp=pb->exp;  
            s->coef=pb->coef;  
            tc->next=s;  
            tc=s;  
            pb=pb->next;  
        }  
        else                //pa->exp=pb->exp  
        {  
            c=pa->coef+pb->coef;  
            if (c!=0)         
            {  
                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) pa=pb;      
    while (pa!=NULL)  
    {  
        s=(PolyNode *)malloc(sizeof(PolyNode));  
        s->exp=pa->exp;  
        s->coef=pa->coef;  
        tc->next=s;  
        tc=s;  
        pa=pa->next;  
    }  
    tc->next=NULL;  
}  
  
int main()  
{  
    PolyNode *ha,*hb,*hc;  
    PolyArray a[]= {{1.2,0},{2.5,1},{3.2,3},{-2.5,5}};  
    PolyArray b[]= {{-1.2,0},{2.5,1},{3.2,3},{2.5,5},{5.4,10}};  
    CreateListR(ha,a,4);  
    CreateListR(hb,b,5);  
    printf("原多项式A:   ");  
    DispPoly(ha);  
    printf("原多项式B:   ");  
    DispPoly(hb);  
    Sort(ha);  
    Sort(hb);  
    printf("有序多项式A: ");  
    DispPoly(ha);  
    printf("有序多项式B: ");  
    DispPoly(hb);  
    Add(ha,hb,hc);  
    printf("多项式相加:  ");  
    DispPoly(hc);  
    DestroyList(ha);  
    DestroyList(hb);  
    DestroyList(hc);  
    return 0;  
}