下面是定义二次多项式ax2+bx+c所对应的类:

#include#includeClassQuadratic{doublea,b,c;public:Quadratic(){a=b=c=0;}Quadratic(doubleaa,Quadraticbb,doublecc);Quadraticopetator＋(Quadratic&x);Quadraticoperator－(Quadratic&x);doubleCompute(doublex);intRoot(double&r1,doub