线性结构CT 02-线性结构1 一元多项式的乘法与加法运算

  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 typedef struct PolyNode *Polynomial;
  4 struct PolyNode 
  5 {
  6     int coef;
  7     int expon;
  8     struct PolyNode *next;
  9 };
 10 
 11 Polynomial ReadPoly();
 12 void Attach(int c,int e,Polynomial *pReal);
 13 Polynomial Add(Polynomial P1,Polynomial P2);
 14 Polynomial Mult(Polynomial P1,Polynomial P2);
 15 void PrintPoly(Polynomial P);
 16 
 17 int main()
 18 {
 19     Polynomial P1,P2,PMult,PSum;
 20     P1 = ReadPoly();
 21     P2 = ReadPoly();
 22     PMult = Mult(P1,P2);
 23     PrintPoly(PMult);
 24     PSum = Add(P1,P2);
 25     PrintPoly(PSum);
 26     return 0;
 27 }
 28 Polynomial ReadPoly()
 29 {
 30     Polynomial P,Rear,t;
 31     int c,e,N;
 32     scanf("%d",&N);
 33     P = (Polynomial)malloc(sizeof(struct PolyNode));
 34     P->next = NULL;
 35     Rear = P;
 36     while(N--){
 37         scanf("%d %d",&c,&e);
 38         Attach(c,e,&Rear);
 39     }
 40     t = P;
 41     P = P->next;
 42     free(t);
 43     return P;
 44 }
 45 void Attach(int c,int e,Polynomial *pReal)
 46 {
 47     Polynomial P;
 48     P = (Polynomial)malloc(sizeof(struct PolyNode));
 49     P->coef = c;
 50     P->expon = e;
 51     P->next = NULL;
 52     (*pReal)->next = P;
 53     *pReal = P;
 54 }
 55 
 56 Polynomial Add(Polynomial P1,Polynomial P2)
 57 {
 58     Polynomial P,t1,t2,t,Rear;
 59     if(!P1 && !P2){  
 60         if(!P1)
 61             return P2;
 62         else
 63             return P1;
 64     }
 65     P = (Polynomial)malloc(sizeof(struct PolyNode));
 66     P->next = NULL;
 67     Rear = P;
 68     t1 = P1;
 69     t2 = P2;
 70     while(t1 && t2){
 71         if(t1->expon == t2->expon){
 72             if(t1->coef + t2->coef) 
 73                 Attach(t1->coef + t2->coef,t1->expon,&Rear);
 74             t1 = t1->next;
 75             t2 = t2->next;
 76         }
 77         else if(t1->expon > t2->expon){
 78             if(t1->coef)
 79                 Attach(t1->coef,t1->expon,&Rear);
 80             t1 = t1->next;
 81         }
 82         else{
 83             if(t2->coef)
 84                 Attach(t2->coef,t2->expon,&Rear);
 85             t2 = t2->next;
 86         }
 87     }
 88     while(t1){
 89         if(t1->coef)
 90             Attach(t1->coef,t1->expon,&Rear);
 91         t1 = t1->next; 
 92     } 
 93     while(t2){
 94         if(t2->coef)
 95             Attach(t2->coef,t2->expon,&Rear);
 96         t2 = t2->next; 
 97     }
 98     t = P;
 99     P = P->next;
100     free(t);
101     return P;
102 }
103 Polynomial Mult(Polynomial P1,Polynomial P2)
104 {
105     Polynomial P,t1,t2,t,Rear;
106     int c,e;
107     if(!P1 || !P2)
108         return NULL;
109     t1 = P1;
110     t2 = P2;
111     P = (Polynomial)malloc(sizeof(struct PolyNode));
112     P->next = NULL;
113     Rear = P;
114     while(t2){
115         if(t1->coef * t2->coef){
116             Attach(t1->coef * t2->coef,t1->expon + t2->expon,&Rear); 
117         }
118         t2 = t2->next;
119     }
120     t1 = t1->next;
121     while(t1){
122         t2 = P2;
123         Rear = P;
124         while(t2){
125             e = t1->expon + t2->expon;
126             c = t1->coef * t2->coef;
127             while(Rear->next && Rear->next->expon > e)
128                 Rear = Rear->next;
129             if(Rear->next && Rear->next->expon == e){
130                 if(Rear->next->coef + c)
131                     Rear->next->coef += c;
132                 else{
133                     t = Rear->next;
134                     Rear->next = t->next;
135                     free(t);
136                 }
137             }
138             else{
139                 if(c){
140                     t = (Polynomial)malloc(sizeof(struct PolyNode));
141                     t->coef = c;
142                     t->expon = e;
143                     t->next = Rear->next;
144                     Rear->next = t;
145                     Rear = Rear->next;
146                 }
147             }
148         t2 = t2->next;
149         }
150     t1 = t1->next;
151     }
152     t2 = P;
153     P = P->next;
154     free(t2);
155     return P;
156 }
157 void PrintPoly(Polynomial P)
158 {
159     int flag = 0;
160     if(!P)
161         printf("0 0");
162     while(P){
163         if (!flag)
164             flag = 1;
165         else
166             printf(" ");
167         printf("%d %d", P->coef, P->expon);
168         P = P->next;
169     }
170     printf("\n");
171 }