classes

#define _USE_MATH_DEFINES
#include <cmath>
#include <cstdio>

double lenght(int x1, int y1, int x2, int y2)
{

}

class CShape
{
public:
    CShape();
    ~CShape();
    virtual void Area() = 0;
    virtual void IsPointInside() = 0;
};

CShape::CShape()
{
}

CShape::~CShape()
{
}

class CRect: public CShape
{
public:
    CRect() : CShape() {};
    ~CRect();
    void Area() { printf("%d\n", (right - left) * (bottom - top)); }
    void IsPointInside(int x, int y)
    {
        if (x >= left && x <= right && y >= bottom && y <= top)
            printf("YES\n");
        else
            printf("NO\n");
    }
private:
    int top;
    int left;
    int bottom;
    int right;
};

CRect::CRect() : CShape()
{
}

CRect::~CRect()
{
}

class CCircle: public CShape
{
public:
    CCircle() : CShape() {};
    ~CCircle();
    void Area() { printf("%d\n", rad * rad * M_PI); }
    void IsPointInside(int x, int y)
    {
        double len = length(x, y, xc, yc);
    }

private:
    int xc;
    int yc;
    double rad;
};

CCircle::CCircle() : CShape()
{
}

CCircle::~CCircle()
{
}

class CTriangle:public CShape
{
public:
    CTriangle() : CShape() {};
    ~CTriangle();
    void Area() { printf("\n"); }

private:
    int x1;
    int y1;
    int x2;
    int y2;
    int x3;
    int y3;
};

CTriangle::CTriangle() :CShape()
{
}

CTriangle::~CTriangle()
{
}