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#2
rjsp2017-11-23 09:26
Complex operator+(Complex &c1,Complex &c2);
为什么不加 const ？ Complex operator+(const Complex &c1,const Complex &c2) 当然，其它的也很歪，建议换本教科书  程序代码：#include <iostream> class Complex { public: Complex( double real=0, double imag=0 ); private: double real_; double imag_; friend Complex operator+( const Complex& lhs, const Complex& rhs ); friend std::ostream& operator<<( std::ostream& os, const Complex& c ); }; #include <iomanip> using namespace std; Complex::Complex( double real, double imag ) : real_(real), imag_(imag) { } Complex operator+( const Complex& lhs, const Complex& rhs ) { return Complex( lhs.real_+rhs.real_, lhs.imag_+rhs.imag_ ); } std::ostream& operator<<( std::ostream& os, const Complex& c ) { os << '(' << c.real_; if( c.imag_ != 0 ) { ios::fmtflags flag = os.flags(); os << setiosflags(ios::showpos) << c.imag_ << 'i'; os.flags( flag ); } return os << ')'; } int main( void ) { Complex c1(2,1); cout << "c1+2.5 = " << (c1+2.5) << endl; } |
#include <iostream>
#include <cmath>
using namespace std;
class Complex
{
public:
Complex();
Complex(double r);
Complex(double r,double i);
void display();
friend Complex operator+(Complex &c1,Complex &c2);
private:
double real;
double imag;
};
Complex::Complex()
{
real=0;
imag=0;
}
Complex::Complex(double r)
{
real=r;
imag=0;
}
Complex::Complex(double r,double i)
{
real=r;
imag=i;
}
Complex operator+(Complex &c1,Complex &c2)
{
return Complex(c1.real+c2.real,c1.imag+c2.imag);
}
void Complex::display()
{
if(imag>0)
cout<<"("<<real<<"+"<<imag<<"i)"<<endl;
else if(imag==0)
cout<<"("<<real<<")"<<endl;
else
cout<<"("<<real<<"-"<<fabs(imag)<<"i)"<<endl;
}
int main()
{
Complex c1(2,1),c;
c=c1+2.5; // 把这行注释掉能编译通过，编译器报错说我的重载+函数有问题。但是我没找出来。还请各位指教。
cout<<"c1+2.5=";
c.display();
return 0;
}
好的谢谢 