#include <iostream>

using namespace std;
struct Point
{
    double x, y;

    Point(){x=y=0;}
    Point(double x, double y)
    {
        this->x=x;
        this->y=y;
    }
};

struct Rectangle
{
    Point topLeft;
    double width, height;

    Rectangle(Point topLeft, double width, double height)
    {
        this->topLeft = topLeft;
        this->width = width;
        this->height = height;
    }
};

//Връща дължината на общата част на отсечките (a1, b1) и (a2, b2)
double segmentIntersectionLength(double a1, double b1, double a2, double b2)
{
    return max(min(b1, b2) - max(a1, a2),0.0);
}

double getIntersectionArea(const Rectangle &r1, const Rectangle &r2)
{
    double horizontalIntersection  =
        segmentIntersectionLength(r1.topLeft.x, r1.topLeft.x + r1.width, r2.topLeft.x, r2.topLeft.x + r2.width);

    double verticalIntersection =
        segmentIntersectionLength(r1.topLeft.y-r1.height, r1.topLeft.y, r2.topLeft.y-r2.height, r2.topLeft.y);

    double rectangleIntersectionArea = horizontalIntersection * verticalIntersection;

    return rectangleIntersectionArea;
}

int main()
{
    Point a(1,7);
    Point b(3,5);
    Rectangle r1(a,5,7);
    Rectangle r2(b,4,3);
    cout<<getIntersectionArea(r1,r2);

    return 0;
}