第九周实验报告（5）

#include "iostream"
using namespace std;
class CEquation
{
private:
double a;     // 未知数系数
double b;     // 常数项
char unknown; // 未知数的符号
public:
CEquation(double aa=0,double bb=0);
friend istream &operator >> (istream &in,CEquation &e);
friend ostream &operator << (ostream &out,CEquation &e);
double Solve();
char getUnknown();
};

CEquation::CEquation(double aa,double bb):a(aa),b(bb){}

istream &operator >> (istream &in,CEquation &e)
{
double d;
char c;
in>>e.a>>e.unknown>>e.b>>c>>d;
return in;
}

ostream &operator << (ostream &out,CEquation &e)
{
if(e.b >=0)
{
out<<e.a<<'x'<<'+'<<e.b<<'='<<'0'<<endl;
}
else
{
out<<e.a<<'x'<<e.b<<'='<<'0'<<endl;
}
return out;
}

double CEquation::Solve()
{
return ((-b)/a);
}

char CEquation::getUnknown()
{
return unknown;
}

int main()
{
CEquation e,m;
cout<<"请输入一元一次方程(输入格式：3x-8=0)：";
cin>>e;
cout<<"方程为："<<e;
cout<<"方程的解为："<<e.getUnknown()<<"="<<e.Solve()<<endl;
cout<<"请输入一元一次方程(输入格式：5s+18=0)：";
cin>>m;
cout<<"方程为："<<m;
cout<<"方程的解为："<<m.getUnknown()<<"="<<m.Solve()<<endl;
m.Solve ();
system("pause");
return 0;
}