Java Регулярний Багатокутник

interface RegularPolygon {
  int getNumSides();
  double getSideLength();

  static int totalSides(RegularPolygon[] rpArray) {
  }

  default double getPerimeter() {
  }
  default double getInteriorAngle() {
  }
}

class EquilateralTriangle implements RegularPolygon {
  private double sideLength;

  public EquilateralTriangle(double sideLength) {
  }

  public int getNumSides() {
  }

  public double getSideLength() {
  }

  public String toString() {
  }
}

class Square implements RegularPolygon {
  private double sideLength;

  public Square(double sideLength) {
  }

  public int getNumSides() {
  }

  public double getSideLength() {
  }

  public String toString() {
  }
}

public class Main {
  public static void main(String[] args) {
    Scanner con = new Scanner(System.in);
    int n = con.nextInt();
    RegularPolygon[] rpArray = new RegularPolygon[n];
    ...
    con.close();
  }
}