/*一元多项式求乘积*/
#include<stdio.h>#include<time.h>#include<stdlib.h>
void init_num(int x[],int y[]){ /* int i; srand( (unsigned)time( NULL ) ); for(i=0;i<65536;i++) { srand( (unsigned)time( NULL ) ); x[i]=rand(); srand( (unsigned)time( NULL ) ); y[i]=rand(); }*/
}
void show(int a[],int MaxLen){ int i; int first=0; for(i=0;i<=MaxLen;i++) { if(a[i]!=0) { if(i!=MaxLen) { if(first==0) { first++; printf("%dX(%d)",a[i],i); } else { printf(" + %dX(%d) ",a[i],i); } }
} } printf("/n");}
/*采用数组存储一元多项式*/void method_one(int a[], int b[],int c[],int MaxLen_a,int MaxLen_b) //MaxLen只带{ int i,j; for(i=0;i<=MaxLen_a;i++) { for(j=0;j<=MaxLen_b;j++) { c[i+j] += a[i]*b[j]; } }}
/*第二种存储方式，采用链表*/struct Node{ int x;//指示x的幂 int coff; struct Node *next;};
struct Node *Creat_Node(int x,int coff){ struct Node *node=(struct Node *)malloc(sizeof(struct Node)) ; node->coff=coff; node->x=x; node->next=NULL; return node;}//int a[4]={1,0,3,0};struct Node * init_a(void){ struct Node *first; first=Creat_Node(0,1); first->next=Creat_Node(2,3); return first;}//int b[4]={0,3,2,1};struct Node * init_b(void){ struct Node *first; first=Creat_Node(1,3); first->next=Creat_Node(2,2); first->next->next=Creat_Node(3,1); return first;}
void show_link(struct Node *node){ int first=0; struct Node *p=node; while( p!=NULL ) { if(p->coff!=0) { if(first==0) { first=1; printf("%dX(%d)",p->coff,p->x); } else { printf(" + %dX(%d) ",p->coff,p->x); } } p=p->next; } printf("/n");}
struct Node * mul(struct Node * a,struct Node * b){ struct Node * first; struct Node *p1,*p2; first=Creat_Node(0,0); p1=a; while(p1!=NULL) { p2=b; while(p2!=NULL) { { int M=p1->x+p2->x; int COFF=p1->coff*p2->coff; struct Node *p=first; for(; p->next!=NULL;p=p->next) { if(p->x==M) { p->coff +=COFF; } } if(p->next==NULL) { if(p->x==M) { p->coff +=COFF; } else { p->next=Creat_Node(M,COFF); } } } p2=p2->next; } p1=p1->next; } return first;}
int main(){ clock_t start,finish; double difTime; int a[4]={1,2,3,0}; int b[4]={2,3,4,1}; int c[7]={0};
struct Node *a1,*a2,*a3; method_one(a,b,c,3,3); show(a,3); show(b,3); show(c,6);
a1=init_a(); show_link(a1); a2=init_b(); show_link(a2); a3=mul(a1,a2); show_link(a3);
start=clock();
finish=clock(); difTime=(double)(finish-start)/CLOCKS_PER_SEC; printf("use %f secons/n",difTime);
return 0;}
