package shapes;

import java.lang.String;
import java.util.Arrays;
import java.util.Collections;

abstract class Shape {
    public abstract String getName();
    public abstract double getMass();
    public abstract void   Scaling( double coef );
}

// Point.java
class Point extends Shape {

        private String _name = "Точка";
        private double x, y, m;

    public Point(double x, double y) {
        this.x = x;
        this.y = y;
        this.m = 0;
    }

        public Point(double x, double y, double m) {
        this.x = x;
        this.y = y;
        this.m = m;
    }

    public double getX() {
            return this.x;
    }

    public double getY() {
            return this.y;
    }

    public void setX(double x) {
            this.x = x;
    }

    public void setY(double y) {
            this.x = y;
    }

    @Override
    public String getName() {
        return this._name;
    }

    @Override
    public double getMass() {
        return m;
    }

    @Override
    public void Scaling(double coef) {
            x = x * coef;
            y = y * coef;
        }
}

// Line.java
class Line extends Shape {

        private String _name = "Линия";

        private Point P1, P2;
        private double p;

    public Line(Point P1, Point P2, double p) {
        this.P1 = P1;
        this.P2 = P2;
        this.p = p;
    }

    @Override
    public String getName() {
        return this._name;
    }

    @Override
    public double getMass() {
        return Math.sqrt((P1.getX() - P2.getX()) * (P1.getX() - P2.getX()) + (P1.getY() - P2.getY()) * (P1.getY() - P2.getY())) * p;
    }

    @Override
    public void Scaling(double coef) {
            double oldMass = this.getMass();

            P1.setX( P1.getX() * coef );
            P1.setY( P1.getY() * coef );
            P2.setX( P2.getX() * coef );
            P2.setY( P2.getY() * coef );
            p = p * oldMass / this.getMass();
        }
}

// Ellipse.java
class Ellipse extends Shape {

        private String _name = "Эллипс";

        private Point P;
        private double rx, ry, p;

    public Ellipse(Point P, double rx, double ry, double p) {
        this.P = P;
        this.rx = rx;
        this.ry = ry;
        this.p = p;
    }

    @Override
    public String getName() {
        return this._name;
    }

    @Override
    public double getMass() {
        return 4 * ( ( Math.PI * rx * ry + ( rx - ry ) * ( rx - ry ) ) / ( rx + ry ) ) * p;
    }

    @Override
    public void Scaling(double coef) {
            double oldMass = this.getMass();

            P.setX( P.getX() * coef );
            P.setY( P.getY() * coef );
            rx = rx * coef;
            ry = ry * coef;
            p = p * oldMass / this.getMass();

        }
}

// Triangle.java
class Triangle extends Shape {

        private String _name = "Треугольник";

        private Point P1, P2, P3;
        private double p;

    public Triangle(Point P1, Point P2, Point P3, double p) {
        this.P1 = P1;
        this.P2 = P2;
        this.P3 = P3;
        this.p = p;
    }

    @Override
    public String getName() {
        return this._name;
    }

    @Override
    public double getMass() {
        return Math.abs((P2.getX() - P1.getX()) * (P3.getY() - P1.getY()) - (P3.getX() - P1.getX()) * (P2.getY() - P1.getY())) / 2 * p;
    }

    @Override
    public void Scaling(double coef) {
            double oldMass = this.getMass();

            P1.setX( P1.getX() * coef );
            P1.setY( P1.getY() * coef );
            P2.setX( P2.getX() * coef );
            P2.setY( P2.getY() * coef );
            P3.setX( P3.getX() * coef );
            P3.setY( P3.getY() * coef );
            p = p * oldMass / this.getMass();
        }
}

// Polygon.java
class Polygon extends Shape {

        private String _name = "Многоугольник";

        private Point[] Coord;
        private double p;

    public Polygon(Point[] Coord, double p) {
                this.Coord = Coord;
        this.p = p;
    }

    @Override
    public String getName() {
        return this._name;
    }

    @Override
    public double getMass() {
                double s = 0;
                int n = Coord.length;

                for ( int i = 0; i < n; ++i )
                {
                  s += Math.abs( Coord[i].getX() *  Coord[(i + 1) % n].getY() - Coord[(i + 1) % n].getX() *  Coord[i].getY() );
                }
                s *= 0.5;

        return s * p;
    }

    @Override
    public void Scaling(double coef) {
            double oldMass = this.getMass();

            for ( int i = 0; i < Coord.length; ++i ) {
                Coord[i].setX(Coord[i].getX() * coef);
                Coord[i].setY(Coord[i].getY() * coef);
            }
            p = p * oldMass / this.getMass();
        }
}

class Shapes {

    private Shape[] shapes;

    public Shapes(Shape[] shapes) {
            this.shapes = shapes;
    }

    public double getTotalMass() {
            double m = 0;
            for (int i = 0; i < shapes.length; i++) {
                    m += shapes[i].getMass();
            }
            return m;
    }

    public double getAverageMass() {
            return getTotalMass() / shapes.length;
    }

    public void Shuffle() {
        Collections.shuffle(Arrays.asList(shapes));
    }

    public void Print() {
        for( int i = 0; i < shapes.length; i++ ){
            System.out.println( (i + 1) + ". " + shapes[i].getName() + ",  масса: " + shapes[i].getMass());
        }
    }

    public void DeleteMinimal( int num ) {
        for( int i = 0; i < num; i++ ) {
            double minMass = shapes[0].getMass();
            int index = 0;

            for( int j = 1; j < shapes.length; j++ ) {

                 if ( shapes[j].getMass() < minMass) {
                        minMass = shapes[j].getMass();
                        index = j;
                }
            }

            // Удалить элемент  index  массива  shapes[]

        }
    }

    public void Scaling(double koef) {
        for (int i = 0; i < shapes.length; i++){
            shapes[i].Scaling( koef );
        }
    }

    public static void main(String[] args) {

            Shapes ShapeSystem = new Shapes(new Shape[] {
                    new Point(1, 2, 3),
                    new Point(2, 1, 4),
                    new Line(new Point(1, 5), new Point(7, 6), 6),
                    new Triangle(new Point(1, 5), new Point(7, 6), new Point(3, 7), 1),
                    new Polygon(new Point[] {new Point(1, 5), new Point(7, 6), new Point(9, 7)}, 4),
            });

            ShapeSystem.Print();

            System.out.println("Суммарная масса: " + ShapeSystem.getTotalMass());

            ShapeSystem.Shuffle();
            ShapeSystem.Print();

            ShapeSystem.Scaling( 1.35 );

            System.out.println("Суммарная масса: " + ShapeSystem.getTotalMass());

            ShapeSystem.DeleteMinimal( 3 );
            ShapeSystem.Print();
    }
}