程序代码：

#include <iostream>
#include <cmath>
using namespace std;
class point{

public:
    point(int xx,int yy)
    {
        x=xx;y=yy;
    }
    point(){};
    ~point(){}

    point(point &p)
    {
        x=p.x;y=p.y;
    }

    int getx(){return x;}
    int gety(){return y;}

private:
    int x,y;
};


class line{

public:

    line(point pt1,point pt2):p1(pt1),p2(pt2)
    {
        double k=(p2.gety()-p1.gety())/(p2.getx()-p1.getx());    //求出斜率K
        double b=(p1.gety()-k*p1.getx());            //求出b
    }
    line(){}

    line(line &l):p1(l.p1),p2(l.p2)
    {
        k=l.k;b=l.b;
    }

friend point jd(line &l1,line &l2)
{
    point p((l1.b-l2.b)/(l2.k-l1.k),l1.k*(l1.b-l2.b)/(l2.k-l1.k));

    return p;
}



private:    
    point p1,p2;
    double k,b;
};





void main()
{
    point p1(0,0),p2(2,2),p3(0,2),p4(2,0);   //初始化4点
    line l1(p1,p2),l2(p3,p4);        //两条不相交的直线
    point px(jd(l1,l2));
    cout<<px.getx()<<"\t"<<px.gety()<<endl;
}