Question

怎么用C++实现一个多项式类啊，使它支持加减乘法啊！

如：能够进行以下运算的：多项式+多项式；

常量+多项式；多项式+常量；

多项式-多项式；

常量-多项式；多项式-常量；

多项式*多项式；

常量*多项式；多项式*常量。

Answer 1

提示1：多项式类的声明如下州粗：
class polynomial
{
public:
polynomial(){ for(int i=0;i<30;i++) coef[i]=0; }//构造函数
void assign_coef(double coefficient,unsigned int exponent); //将多项式中指数为
//exponent的项的系数设置成coefficient
void view_coef() const; //显示多项式
private:
double coef[30]; //存放多项式系数的数组，该多项式最多有30项
unsigned int current_degree; //存放该多项式的指数值
};
提示2：主函数程序如下：其中定义了一个含三个多项式的对象数组：p[3]
void print_menu();
char get_command();
int set_current();
void test_assign(polynomial& test);
void main(){
polynomial p[3];
int current_index=0,i;
char command;
do{
print_menu();
command=get_command();
switch(command){
case 's':
current_index=set_current();
break;
case 'l':
test_assign(p[current_index]);
break;
case 'v':
cout<<char(current_index+'a')<<":";
p[current_index].view_coef();
break;
case 'q':
break;
default:
cout<<"Invalid command."<<册没镇endl;
}
}while(command!='q');
}
void print_menu(){
cout<<"---------------The Commands---------------"<<endl;
cout<<"s - set the current polynomial to work on"<<endl;
cout<<"l - use the assign_coef function"<<endl;
cout<<"v - use the view_coef function"<<endl;
cout<<"q - quit"<<endl;
cout<<"------------------------------------------"<<endl;
}
char get_command(){
char command;
cout<<">";
cin>>command;
return(command);
}
int set_current(){
char command;

do{
cout<<"Enter the polynomial you want to work on:(a,b,c)";
command=get_command();
}while((command<察哗'a')||(command>=char('a'+3)));
return command-'a';
}
void test_assign(polynomial& test){
double coefficient;
unsigned int exponent;
cout<<"Enter exponent:";
cin>>exponent;
cout<<"Enter coefficient:";
cin>>coefficient;
test.assign_coef(coefficient,exponent);
cout<<"After assigning:";
test.view_coef();
}

Answer 2

分值太少了~~~