拷过去后自己整一下编程风格
//一元稀疏多项式计算器
#include
<stdio.h>
#include
<stdlib.h>
#define
OK
1;
#define
READ(I)
while
(((I)=getchar())=='\n');
//读入合法字符
typedef
int
status;
typedef
struct
PolyNode
{
float
coef;
int
expn;
struct
PolyNode
*next;
}Poly,*P_Poly;
status
CreatPoly(P_Poly*,int);
//创建多项式链表
void
OutP_Poly(P_Poly);
//输出多项式
void
AddPoly(P_Poly*,P_Poly,P_Poly);
//求和
void
DecPoly(P_Poly*,P_Poly,P_Poly);
//求差
void
DelPoly(P_Poly*);
//删除并释放多项式
status
main()
{
P_Poly
PolyHead[26]={0};
char
menu,name;
for
(;;)
{
printf
("1.建立多项式\n");
printf
("2.输出多项式\n");
printf
("3.求两个多项式之和(必须先创建),建立和式并输出\n");
printf
("4.求两个多项式之差(必须先创建),建立差式并输出\n");
printf
("5.删除多项式\n");
printf
("6.退出\n");
printf
("请选择指令:");
READ(menu)
switch
(menu)
{
case
'1':
{
int
n;
printf
("请输入要创建的多项式的名称（单个小写字母表示）:");
READ(name)
if
(NULL!=PolyHead[name-'a'])
{
printf
("此多项式已经存在!\n");
break;
}
printf
("请输入项数:");
scanf
("%d",&n);
if(CreatPoly(&PolyHead[name-'a'],n))
printf
("多项式%c创建完毕!\n",name);
break;
}
case
'2':
printf
("请输入要输出的多项式的名称:");
READ(name)
if
(NULL==PolyHead[name-'a'])
{
printf
("此多项式不存在!\n");
break;
}
OutP_Poly(PolyHead[name-'a']);
break;
case
'3':
{
char
name1,name2;
printf
("请输入加式一的名称:");
READ(name1)
if
(NULL==PolyHead[name1-'a'])
{
printf
("此多项式不存在!请先创建\n");
break;
}
printf
("请输入加式二的名称:");
READ(name2)
if
(NULL==PolyHead[name2-'a'])
{
printf
("此多项式不存在!请先创建\n");
break;
}
printf
("请输入要创建的和式的名称:");
READ(name)
if
(NULL!=PolyHead[name-'a'])
{
printf
("此多项式已经存在!\n");
break;
}
AddPoly(&PolyHead[name-'a'],PolyHead[name1-'a'],PolyHead[name2-'a']);
OutP_Poly(PolyHead[name-'a']);
break;
}
case
'4':
{
char
name1,name2;
printf
("请输入被减式的名称:");
READ(name1)
if
(NULL==PolyHead[name1-'a'])
{
printf
("此多项式不存在!请先创建\n");
break;
}
printf
("请输入减式的名称:");
READ(name2)
if
(NULL==PolyHead[name2-'a'])
{
printf
("此多项式不存在!请先创建\n");
break;
}
printf
("请输入要创建的差式的名称:");
READ(name)
if
(NULL!=PolyHead[name-'a'])
{
printf
("此多项式已经存在!\n");
break;
}
DecPoly(&PolyHead[name-'a'],PolyHead[name1-'a'],PolyHead[name2-'a']);
OutP_Poly(PolyHead[name-'a']);
break;
}
case
'5':
printf
("请输入要删除的多项式名称:");
READ(name)
if
(NULL==PolyHead[name-'a'])
{
printf
("此多项式不存在!\n");
break;
}
DelPoly(&PolyHead[name-'a']);
printf
("多项式%c已删除!\n",name);
break;
case
'6':
return
OK;
}
}
}
status
CreatPoly(P_Poly*
P_PolyHead,int
n)
{
//为确保其他子函数正常运行，入口参数要求不含同类项、指数递减
int
i=0;
P_Poly
p,tail;
*P_PolyHead=(Poly*)malloc(sizeof(Poly));
(*P_PolyHead)->expn=n;
tail=*P_PolyHead;
printf
("请按照指数递减序输入最简形式的多项式\n");
for
(;i<n;i++)
{
p=(Poly*)malloc(sizeof(Poly));
printf
("请输入第%d项的系数和指数(系数，指数):",i+1);
scanf
("%f,%d",&(p->coef),&(p->expn));
tail->next=p;
tail=p;
}
tail->next=NULL;
return
OK;
}
void
OutP_Poly(P_Poly
PolyHead)
{
int
i=0;
P_Poly
p;
printf
("%d
",PolyHead->expn);
p=PolyHead->next;
for
(;i<PolyHead->expn;i++)
{
printf
("%f,%d
",p->coef,p->expn);
p=p->next;
}
printf
("\n");
}
void
AddPoly(P_Poly*
P_PolyHead,P_Poly
PolyHead1,P_Poly
PolyHead2)
{
int
i=0;
P_Poly
p1,p2,p,tail;
p1=PolyHead1->next;
p2=PolyHead2->next;
*P_PolyHead=(P_Poly)malloc(sizeof(Poly));
p=tail=*P_PolyHead;
while(p1&&p2)
{
int
e1,e2;
e1=p1->expn;
e2=p2->expn;
if
(e1>e2)
{
p=(P_Poly)malloc(sizeof(Poly));
tail->next=p;
tail=p;
*p=*p1;
p1=p1->next;
i++;
}
else
if(e1==e2)
{
float
sum_c=p1->coef+p2->coef;
if
(sum_c!=0.0)
{
p=(P_Poly)malloc(sizeof(Poly));
tail->next=p;
tail=p;
p->coef=sum_c;
p->expn=e1;
i++;
}
p1=p1->next;
p2=p2->next;
}
else
if
(e1<e2)
{
p=(P_Poly)malloc(sizeof(Poly));
tail->next=p;
tail=p;
*p=*p2;
p2=p2->next;
i++;
}
}
while
(p1)
{
p=(Poly*)malloc(sizeof(Poly));
*p=*p1;
tail->next=p;
tail=p;
p1=p1->next;
i++;
}
while
(p2)
{
p=(Poly*)malloc(sizeof(Poly));
*p=*p2;
tail->next=p;
tail=p;
p2=p2->next;
i++;
}
(*P_PolyHead)->expn=i;
tail->next=NULL;
}
void
DecPoly(P_Poly*
P_PolyHead,P_Poly
PolyHead1,P_Poly
PolyHead2)
{
int
i=0;
P_Poly
p1,p2,p,tail;
p1=PolyHead1->next;
p2=PolyHead2->next;
*P_PolyHead=(P_Poly)malloc(sizeof(Poly));
p=tail=*P_PolyHead;
while(p1&&p2)
{
int
e1,e2;
e1=p1->expn;
e2=p2->expn;
if
(e1>e2)
{
p=(P_Poly)malloc(sizeof(Poly));
tail->next=p;
tail=p;
*p=*p1;
p1=p1->next;
i++;
}
else
if(e1==e2)
{
float
dif_c=p1->coef-p2->coef;
if
(dif_c!=0.0)
{
p=(P_Poly)malloc(sizeof(Poly));
tail->next=p;
tail=p;
p->coef=dif_c;
p->expn=e1;
i++;
}
p1=p1->next;
p2=p2->next;
}
else
if
(e1<e2)
{
p=(P_Poly)malloc(sizeof(Poly));
tail->next=p;
tail=p;
p->coef=-p2->coef;
p->expn=p2->expn;
p2=p2->next;
i++;
}
}
while
(p1)
{
p=(Poly*)malloc(sizeof(Poly));
*p=*p1;
tail->next=p;
tail=p;
p1=p1->next;
i++;
}
while
(p2)
{
p=(Poly*)malloc(sizeof(Poly));
*p=*p2;
tail->next=p;
tail=p;
p2=p2->next;
i++;
}
(*P_PolyHead)->expn=i;
tail->next=NULL;
}
void
DelPoly(P_Poly*
P_PolyHead)
{
P_Poly
p,prior;
p=prior=*P_PolyHead;
while
(p->next)
{
p=p->next;
free(prior);
prior=p;
}
*P_PolyHead=NULL;
}