一元多项式的乘法与加法运算

4 3 4 -5 2  6 1  -2 0
3 5 20  -7 4  3 1

15 24 -25 22 30 21 -10 20 -21 8 35 6 -33 5 14 4 -15 3 18 2 -6 1
5 20 -4 4 -5 2 9 1 -2 0

  1 #include <stdio.h>
  2 
  3 typedef struct PolyNode
  4 {
  5     int coef;
  6     int expon;
  7     struct PolyNode *link;
  8 }*Polynomial;
  9 
 10 void Attach(int a,int b,Polynomial *pRear)
 11 {
 12     Polynomial P;
 13     P=(Polynomial)malloc(sizeof(struct PolyNode));
 14     P->coef=a;
 15     P->expon=b;
 16     P->link=NULL;
 17     (*pRear)->link=P;
 18     *pRear=P;
 19 }
 20 
 21 Polynomial ReadPoly()
 22 {
 23     Polynomial P,Rear,t;
 24     int n,a,b;
 25     scanf("%d",&n);
 26     P=(Polynomial)malloc(sizeof(struct PolyNode));
 27     P->link=NULL;
 28     Rear=P;
 29     while(n--)
 30     {
 31         scanf("%d %d",&a,&b);
 32         Attach(a,b,&Rear);
 33     }
 34     t=P;
 35     P=P->link;
 36     free(t);
 37     return P;
 38 }
 39 
 40 Polynomial Add(Polynomial P1,Polynomial P2)
 41 {
 42     Polynomial front,rear,temp;
 43     int sum;
 44     rear=(Polynomial)malloc(sizeof(struct PolyNode));
 45     front=rear;
 46     while(P1&&P2)
 47     {
 48         if(P1->expon>P2->expon)
 49         {
 50             Attach(P1->coef,P1->expon,&rear);
 51             P1=P1->link;
 52         }
 53         if(P1->expon<P2->expon)
 54         {
 55             Attach(P2->coef,P2->expon,&rear);
 56             P2=P2->link;
 57         }
 58         if(P1->expon==P2->expon)
 59         {
 60             sum=P1->coef+P2->coef;
 61             if(sum)
 62             {
 63                 Attach(sum,P1->expon,&rear);
 64             }
 65             P1=P1->link;
 66             P2=P2->link;
 67         }
 68     }
 69     for(;P1;P1=P1->link) Attach(P1->coef,P1->expon,&rear);
 70     for(;P2;P2=P2->link) Attach(P2->coef,P2->expon,&rear);
 71     rear->link=NULL;
 72     temp=front;
 73     front=front->link;
 74     free(temp);
 75     return front; 
 76 }
 77 
 78 Polynomial Mult(Polynomial P1,Polynomial P2)
 79 {
 80     Polynomial P,Rear,t1,t2,t;
 81     int a,b;
 82     if(!P1||!P2) return NULL;
 83     t1=P1;
 84     t2=P2;
 85     P=(Polynomial)malloc(sizeof(struct PolyNode));
 86     P->link=NULL;
 87     Rear=P;
 88     while(t2)
 89     {
 90         Attach(t1->coef*t2->coef,t1->expon+t2->expon,&Rear);
 91         t2=t2->link;
 92     }
 93     t1=t1->link;
 94     while(t1)
 95     {
 96         t2=P2;
 97         Rear=P;
 98         while(t2)
 99         {
100             a=t1->coef*t2->coef;
101             b=t1->expon+t2->expon;
102             while(Rear->link&&Rear->link->expon>b)
103             {
104                 Rear=Rear->link;
105             }
106             if(Rear->link&&Rear->link->expon==b)
107             {
108                 if(Rear->link->coef+a)
109                     Rear->link->coef+=a;
110                 else
111                 {
112                     t=Rear->link;
113                     Rear->link=t->link;
114                     free(t);
115                 }
116             }
117             else
118             {
119                 t=(Polynomial)malloc(sizeof(struct PolyNode));
120                 t->coef=a;
121                 t->expon=b;
122                 t->link=Rear->link;
123                 Rear->link=t;
124                 Rear=Rear->link;
125             }
126             t2=t2->link;
127         }
128         t1=t1->link;
129     }
130     t2=P;
131     P=P->link;
132     free(t2);
133     return P;
134 }
135 
136 void PrintPoly(Polynomial P)
137 {
138     int flag=0;
139     if(!P)
140     {
141         printf("0 0\n");
142         return ;
143     }
144     while(P)
145     {
146         if(!flag) flag=1;
147         else printf(" ");
148         printf("%d %d",P->coef,P->expon);
149         P=P->link;
150     }
151     printf("\n");
152 }
153 
154 int main()
155 {
156     Polynomial P1,P2,PP,PS;
157     
158     P1=ReadPoly();
159     P2=ReadPoly();
160     PP=Mult(P1,P2);
161     PrintPoly(PP);
162     PS=Add(P1,P2);
163     PrintPoly(PS);
164      
165     return 0;
166 }