include "math.h"

class point

{

public:

float x;

float y;

//建構函式

point(float x,float y)

{

this->x=x;

this->y=y;

}

};

class line

{

float a;

float b;

float c;

public:

//建構函式

line(float a,float b,float c)

{

this->a=a;

this->b=b;

this->c=c;

}

float getDistance(point p)

{

float x,y;

x=p.x;

y=p.y;

return fabs(a*x+b*y+c)/sqrt(a*a+b*b);

}

};

void main()

{

float x,y;

cout<<"請輸入點的X座標:";

cin>>x;

cout<<"請輸入點的Y座標:";

cin>>y;

point p(x,y);

float a,b,c;

cout<<"請輸入a:";

cin>>a;

cout<<"請輸入b:";

cin>>b;

cout<<"請輸入c:";

cin>>c;

line l(a,b,c);

cout<<"點到直線的距離為:"<<l.getDistance(p)<<endl;

}